x^8=-3 (уравнение) Учитель очень удивится увидев твоё верное решение 😼
Найду корень уравнения: x^8=-3
Решение
Подробное решение
Дано уравнениеx 8 = − 3 x^{8} = -3 x 8 = − 3 Т.к. степень в ур-нии равна = 8 и свободный член = -3 < 0, зн. действительных решений у соотв. ур-ния не существует Остальные 8 корня(ей) являются комплексными. сделаем замену:z = x z = x z = x тогда ур-ние будет таким:z 8 = − 3 z^{8} = -3 z 8 = − 3 Любое комплексное число можно представить так:z = r e i p z = r e^{i p} z = r e i p подставляем в уравнениеr 8 e 8 i p = − 3 r^{8} e^{8 i p} = -3 r 8 e 8 i p = − 3 гдеr = 3 8 r = \sqrt[8]{3} r = 8 3 - модуль комплексного числа Подставляем r:e 8 i p = − 1 e^{8 i p} = -1 e 8 i p = − 1 Используя формулу Эйлера, найдём корни для pi sin ( 8 p ) + cos ( 8 p ) = − 1 i \sin{\left(8 p \right)} + \cos{\left(8 p \right)} = -1 i sin ( 8 p ) + cos ( 8 p ) = − 1 значитcos ( 8 p ) = − 1 \cos{\left(8 p \right)} = -1 cos ( 8 p ) = − 1 иsin ( 8 p ) = 0 \sin{\left(8 p \right)} = 0 sin ( 8 p ) = 0 тогдаp = π N 4 + π 8 p = \frac{\pi N}{4} + \frac{\pi}{8} p = 4 π N + 8 π где N=0,1,2,3,... Перебирая значения N и подставив p в формулу для z Значит, решением будет для z:z 1 = − 3 8 1 2 − 2 4 + 3 8 i 2 4 + 1 2 z_{1} = - \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} + \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} z 1 = − 8 3 2 1 − 4 2 + 8 3 i 4 2 + 2 1 z 2 = 3 8 1 2 − 2 4 − 3 8 i 2 4 + 1 2 z_{2} = \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} - \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} z 2 = 8 3 2 1 − 4 2 − 8 3 i 4 2 + 2 1 z 3 = − 3 8 2 4 + 1 2 − 3 8 i 1 2 − 2 4 z_{3} = - \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} - \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} z 3 = − 8 3 4 2 + 2 1 − 8 3 i 2 1 − 4 2 z 4 = 3 8 2 4 + 1 2 + 3 8 i 1 2 − 2 4 z_{4} = \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} + \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} z 4 = 8 3 4 2 + 2 1 + 8 3 i 2 1 − 4 2 z 5 = − 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 i 1 2 − 2 4 2 + 2 ⋅ 3 8 i 2 4 + 1 2 2 z_{5} = - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} z 5 = − 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 i 2 1 − 4 2 + 2 2 ⋅ 8 3 i 4 2 + 2 1 z 6 = 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 i 2 4 + 1 2 2 + 2 ⋅ 3 8 i 1 2 − 2 4 2 z_{6} = \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} z 6 = 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 i 4 2 + 2 1 + 2 2 ⋅ 8 3 i 2 1 − 4 2 z 7 = − 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 1 2 − 2 4 2 − 2 ⋅ 3 8 i 1 2 − 2 4 2 + 2 ⋅ 3 8 i 2 4 + 1 2 2 z_{7} = - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} z 7 = − 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 2 1 − 4 2 − 2 2 ⋅ 8 3 i 2 1 − 4 2 + 2 2 ⋅ 8 3 i 4 2 + 2 1 z 8 = − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 − 2 ⋅ 3 8 i 2 4 + 1 2 2 − 2 ⋅ 3 8 i 1 2 − 2 4 2 z_{8} = - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} z 8 = − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 − 2 2 ⋅ 8 3 i 4 2 + 2 1 − 2 2 ⋅ 8 3 i 2 1 − 4 2 делаем обратную заменуz = x z = x z = x x = z x = z x = z Тогда, окончательный ответ:x 1 = − 3 8 1 2 − 2 4 + 3 8 i 2 4 + 1 2 x_{1} = - \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} + \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} x 1 = − 8 3 2 1 − 4 2 + 8 3 i 4 2 + 2 1 x 2 = 3 8 1 2 − 2 4 − 3 8 i 2 4 + 1 2 x_{2} = \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} - \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} x 2 = 8 3 2 1 − 4 2 − 8 3 i 4 2 + 2 1 x 3 = − 3 8 2 4 + 1 2 − 3 8 i 1 2 − 2 4 x_{3} = - \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} - \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} x 3 = − 8 3 4 2 + 2 1 − 8 3 i 2 1 − 4 2 x 4 = 3 8 2 4 + 1 2 + 3 8 i 1 2 − 2 4 x_{4} = \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} + \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} x 4 = 8 3 4 2 + 2 1 + 8 3 i 2 1 − 4 2 x 5 = − 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 i 1 2 − 2 4 2 + 2 ⋅ 3 8 i 2 4 + 1 2 2 x_{5} = - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} x 5 = − 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 i 2 1 − 4 2 + 2 2 ⋅ 8 3 i 4 2 + 2 1 x 6 = 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 i 2 4 + 1 2 2 + 2 ⋅ 3 8 i 1 2 − 2 4 2 x_{6} = \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} x 6 = 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 i 4 2 + 2 1 + 2 2 ⋅ 8 3 i 2 1 − 4 2 x 7 = − 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 1 2 − 2 4 2 − 2 ⋅ 3 8 i 1 2 − 2 4 2 + 2 ⋅ 3 8 i 2 4 + 1 2 2 x_{7} = - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} x 7 = − 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 2 1 − 4 2 − 2 2 ⋅ 8 3 i 2 1 − 4 2 + 2 2 ⋅ 8 3 i 4 2 + 2 1 x 8 = − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 − 2 ⋅ 3 8 i 2 4 + 1 2 2 − 2 ⋅ 3 8 i 1 2 − 2 4 2 x_{8} = - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} x 8 = − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 − 2 2 ⋅ 8 3 i 4 2 + 2 1 − 2 2 ⋅ 8 3 i 2 1 − 4 2
График
-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 -100 100
___________ ___________
/ ___ / ___
8 ___ / 1 \/ 2 8 ___ / 1 \/ 2
x1 = - \/ 3 * / - - ----- + I*\/ 3 * / - + -----
\/ 2 4 \/ 2 4 x 1 = − 3 8 1 2 − 2 4 + 3 8 i 2 4 + 1 2 x_{1} = - \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} + \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} x 1 = − 8 3 2 1 − 4 2 + 8 3 i 4 2 + 2 1 ___________ ___________
/ ___ / ___
8 ___ / 1 \/ 2 8 ___ / 1 \/ 2
x2 = \/ 3 * / - - ----- - I*\/ 3 * / - + -----
\/ 2 4 \/ 2 4 x 2 = 3 8 1 2 − 2 4 − 3 8 i 2 4 + 1 2 x_{2} = \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} - \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} x 2 = 8 3 2 1 − 4 2 − 8 3 i 4 2 + 2 1 ___________ ___________
/ ___ / ___
8 ___ / 1 \/ 2 8 ___ / 1 \/ 2
x3 = - \/ 3 * / - + ----- - I*\/ 3 * / - - -----
\/ 2 4 \/ 2 4 x 3 = − 3 8 2 4 + 1 2 − 3 8 i 1 2 − 2 4 x_{3} = - \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} - \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} x 3 = − 8 3 4 2 + 2 1 − 8 3 i 2 1 − 4 2 ___________ ___________
/ ___ / ___
8 ___ / 1 \/ 2 8 ___ / 1 \/ 2
x4 = \/ 3 * / - + ----- + I*\/ 3 * / - - -----
\/ 2 4 \/ 2 4 x 4 = 3 8 2 4 + 1 2 + 3 8 i 1 2 − 2 4 x_{4} = \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} + \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} x 4 = 8 3 4 2 + 2 1 + 8 3 i 2 1 − 4 2 / ___________ ___________\ ___________ ___________
| / ___ / ___ | / ___ / ___
| ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2
|\/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - + ----- \/ 2 *\/ 3 * / - - -----
| \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4
x5 = I*|---------------------------- + ----------------------------| + ---------------------------- - ----------------------------
\ 2 2 / 2 2 x 5 = − 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 + i ( 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 ) x_{5} = - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + i \left(\frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2}\right) x 5 = − 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 + i 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 / ___________ ___________\ ___________ ___________
| / ___ / ___ | / ___ / ___
| ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2
|\/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + -----
| \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4
x6 = I*|---------------------------- - ----------------------------| + ---------------------------- + ----------------------------
\ 2 2 / 2 2 x 6 = 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 + i ( − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 ) x_{6} = \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2}\right) x 6 = 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 + i − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 / ___________ ___________\ ___________ ___________
| / ___ / ___ | / ___ / ___
| ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2
|\/ 2 *\/ 3 * / - + ----- \/ 2 *\/ 3 * / - - ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + -----
| \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4
x7 = I*|---------------------------- - ----------------------------| - ---------------------------- - ----------------------------
\ 2 2 / 2 2 x 7 = − 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 1 2 − 2 4 2 + i ( − 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 ) x_{7} = - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2}\right) x 7 = − 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 2 1 − 4 2 + i − 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 / ___________ ___________\ ___________ ___________
| / ___ / ___ | / ___ / ___
| ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2
| \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + -----
| \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4
x8 = I*|- ---------------------------- - ----------------------------| + ---------------------------- - ----------------------------
\ 2 2 / 2 2 x 8 = − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 + i ( − 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 1 2 − 2 4 2 ) x_{8} = - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2}\right) x 8 = − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 + i − 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 2 1 − 4 2
Сумма и произведение корней
[src] / ___________ ___________\ ___________ ___________ / ___________ ___________\ ___________ ___________ / ___________ ___________\ ___________ ___________ / ___________ ___________\ ___________ ___________
| / ___ / ___ | / ___ / ___ | / ___ / ___ | / ___ / ___ | / ___ / ___ | / ___ / ___ | / ___ / ___ | / ___ / ___
___________ ___________ ___________ ___________ ___________ ___________ ___________ ___________ | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2
/ ___ / ___ / ___ / ___ / ___ / ___ / ___ / ___ |\/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - + ----- \/ 2 *\/ 3 * / - - ----- |\/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- |\/ 2 *\/ 3 * / - + ----- \/ 2 *\/ 3 * / - - ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + -----
8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4
0 + - \/ 3 * / - - ----- + I*\/ 3 * / - + ----- + \/ 3 * / - - ----- - I*\/ 3 * / - + ----- + - \/ 3 * / - + ----- - I*\/ 3 * / - - ----- + \/ 3 * / - + ----- + I*\/ 3 * / - - ----- + I*|---------------------------- + ----------------------------| + ---------------------------- - ---------------------------- + I*|---------------------------- - ----------------------------| + ---------------------------- + ---------------------------- + I*|---------------------------- - ----------------------------| - ---------------------------- - ---------------------------- + I*|- ---------------------------- - ----------------------------| + ---------------------------- - ----------------------------
\/ 2 4 \/ 2 4 \/ 2 4 \/ 2 4 \/ 2 4 \/ 2 4 \/ 2 4 \/ 2 4 \ 2 2 / 2 2 \ 2 2 / 2 2 \ 2 2 / 2 2 \ 2 2 / 2 2 ( − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 + i ( − 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 1 2 − 2 4 2 ) ) − ( − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 − i ( 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 ) − i ( − 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 ) − i ( − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 ) ) \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2}\right)\right) - \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} - i \left(\frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2}\right) - i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2}\right) - i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2}\right)\right) − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 + i − 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 2 1 − 4 2 − − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 − i 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 − i − 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 − i − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 / ___________ ___________\ / ___________ ___________\ / ___________ ___________\ / ___________ ___________\
| / ___ / ___ | | / ___ / ___ | | / ___ / ___ | | / ___ / ___ |
| ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 |
|\/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | |\/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | |\/ 2 *\/ 3 * / - + ----- \/ 2 *\/ 3 * / - - ----- | | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- |
| \/ 2 4 \/ 2 4 | | \/ 2 4 \/ 2 4 | | \/ 2 4 \/ 2 4 | | \/ 2 4 \/ 2 4 |
I*|---------------------------- + ----------------------------| + I*|---------------------------- - ----------------------------| + I*|---------------------------- - ----------------------------| + I*|- ---------------------------- - ----------------------------|
\ 2 2 / \ 2 2 / \ 2 2 / \ 2 2 / i ( − 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 1 2 − 2 4 2 ) + i ( − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 ) + i ( − 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 ) + i ( 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 ) i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2}\right) + i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2}\right) + i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2}\right) + i \left(\frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2}\right) i − 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 2 1 − 4 2 + i − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 + i − 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 + i 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 / / ___________ ___________\ ___________ ___________\ / / ___________ ___________\ ___________ ___________\ / / ___________ ___________\ ___________ ___________\ / / ___________ ___________\ ___________ ___________\
| | / ___ / ___ | / ___ / ___ | | | / ___ / ___ | / ___ / ___ | | | / ___ / ___ | / ___ / ___ | | | / ___ / ___ | / ___ / ___ |
/ ___________ ___________\ / ___________ ___________\ / ___________ ___________\ / ___________ ___________\ | | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | | | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | | | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | | | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 | ___ 8 ___ / 1 \/ 2 ___ 8 ___ / 1 \/ 2 |
| / ___ / ___ | | / ___ / ___ | | / ___ / ___ | | / ___ / ___ | | |\/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - + ----- \/ 2 *\/ 3 * / - - ----- | | |\/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | | |\/ 2 *\/ 3 * / - + ----- \/ 2 *\/ 3 * / - - ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | | | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- | \/ 2 *\/ 3 * / - - ----- \/ 2 *\/ 3 * / - + ----- |
| 8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 | |8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 | | 8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 | |8 ___ / 1 \/ 2 8 ___ / 1 \/ 2 | | | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 | | | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 | | | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 | | | \/ 2 4 \/ 2 4 | \/ 2 4 \/ 2 4 |
1*|- \/ 3 * / - - ----- + I*\/ 3 * / - + ----- |*|\/ 3 * / - - ----- - I*\/ 3 * / - + ----- |*|- \/ 3 * / - + ----- - I*\/ 3 * / - - ----- |*|\/ 3 * / - + ----- + I*\/ 3 * / - - ----- |*|I*|---------------------------- + ----------------------------| + ---------------------------- - ----------------------------|*|I*|---------------------------- - ----------------------------| + ---------------------------- + ----------------------------|*|I*|---------------------------- - ----------------------------| - ---------------------------- - ----------------------------|*|I*|- ---------------------------- - ----------------------------| + ---------------------------- - ----------------------------|
\ \/ 2 4 \/ 2 4 / \ \/ 2 4 \/ 2 4 / \ \/ 2 4 \/ 2 4 / \ \/ 2 4 \/ 2 4 / \ \ 2 2 / 2 2 / \ \ 2 2 / 2 2 / \ \ 2 2 / 2 2 / \ \ 2 2 / 2 2 / 1 ( − 3 8 1 2 − 2 4 + 3 8 i 2 4 + 1 2 ) ( 3 8 1 2 − 2 4 − 3 8 i 2 4 + 1 2 ) ( − 3 8 2 4 + 1 2 − 3 8 i 1 2 − 2 4 ) ( 3 8 2 4 + 1 2 + 3 8 i 1 2 − 2 4 ) ( − 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 + i ( 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 ) ) ( 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 + i ( − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 ) ) ( − 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 1 2 − 2 4 2 + i ( − 2 ⋅ 3 8 1 2 − 2 4 2 + 2 ⋅ 3 8 2 4 + 1 2 2 ) ) ( − 2 ⋅ 3 8 2 4 + 1 2 2 + 2 ⋅ 3 8 1 2 − 2 4 2 + i ( − 2 ⋅ 3 8 2 4 + 1 2 2 − 2 ⋅ 3 8 1 2 − 2 4 2 ) ) 1 \left(- \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} + \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}\right) \left(\sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}} - \sqrt[8]{3} i \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}\right) \left(- \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} - \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}\right) \left(\sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}} + \sqrt[8]{3} i \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}\right) \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + i \left(\frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2}\right)\right) \left(\frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2}\right)\right) \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2}\right)\right) \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} + \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2} + i \left(- \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{\sqrt{2}}{4} + \frac{1}{2}}}{2} - \frac{\sqrt{2} \cdot \sqrt[8]{3} \sqrt{\frac{1}{2} - \frac{\sqrt{2}}{4}}}{2}\right)\right) 1 − 8 3 2 1 − 4 2 + 8 3 i 4 2 + 2 1 8 3 2 1 − 4 2 − 8 3 i 4 2 + 2 1 − 8 3 4 2 + 2 1 − 8 3 i 2 1 − 4 2 8 3 4 2 + 2 1 + 8 3 i 2 1 − 4 2 − 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 + i 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 + i − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 − 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 2 1 − 4 2 + i − 2 2 ⋅ 8 3 2 1 − 4 2 + 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 4 2 + 2 1 + 2 2 ⋅ 8 3 2 1 − 4 2 + i − 2 2 ⋅ 8 3 4 2 + 2 1 − 2 2 ⋅ 8 3 2 1 − 4 2 x1 = 0.439015463195998 - 1.05987708533928*i x2 = 1.05987708533928 - 0.439015463195998*i x3 = -0.439015463195998 - 1.05987708533928*i x4 = 0.439015463195998 + 1.05987708533928*i x5 = -1.05987708533928 - 0.439015463195998*i x6 = -1.05987708533928 + 0.439015463195998*i x7 = 1.05987708533928 + 0.439015463195998*i x8 = -0.439015463195998 + 1.05987708533928*i