Сумма корней cos(x)^3-cos(x)^2+cos(x)=1/3

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    Решение

    Сумма и произведение корней [src]
    сумма
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    - re|acos|- - ----------------- + --------------------|| + 2*pi - I*im|acos|- - ----------------- + --------------------|| + - re|acos|- - ----------------- + --------------------|| + 2*pi - I*im|acos|- - ----------------- + --------------------|| + - acos|- - ----- + ----| + 2*pi + I*im|acos|- - ----------------- + --------------------|| + re|acos|- - ----------------- + --------------------|| + I*im|acos|- - ----------------- + --------------------|| + re|acos|- - ----------------- + --------------------|| + acos|- - ----- + ----|
        |    |3     /          ___\            3          ||              |    |3     /          ___\            3          ||       |    |3     /          ___\            3          ||              |    |3     /          ___\            3          ||         \3     3      3  /              |    |3     /          ___\            3          ||     |    |3     /          ___\            3          ||       |    |3     /          ___\            3          ||     |    |3     /          ___\            3          ||       \3     3      3  /
        |    |      |  1   I*\/ 3 |                       ||              |    |      |  1   I*\/ 3 |                       ||       |    |      |  1   I*\/ 3 |                       ||              |    |      |  1   I*\/ 3 |                       ||                                         |    |      |  1   I*\/ 3 |                       ||     |    |      |  1   I*\/ 3 |                       ||       |    |      |  1   I*\/ 3 |                       ||     |    |      |  1   I*\/ 3 |                       ||                         
        |    |    3*|- - + -------|                       ||              |    |    3*|- - + -------|                       ||       |    |    3*|- - - -------|                       ||              |    |    3*|- - - -------|                       ||                                         |    |    3*|- - + -------|                       ||     |    |    3*|- - + -------|                       ||       |    |    3*|- - - -------|                       ||     |    |    3*|- - - -------|                       ||                         
        \    \      \  2      2   /                       //              \    \      \  2      2   /                       //       \    \      \  2      2   /                       //              \    \      \  2      2   /                       //                                         \    \      \  2      2   /                       //     \    \      \  2      2   /                       //       \    \      \  2      2   /                       //     \    \      \  2      2   /                       //                         
    acos(233+13+2233)+(((re(acos(13233(12+3i2)+223(12+3i2)3))+iim(acos(13233(12+3i2)+223(12+3i2)3)))+((acos(233+13+2233)+2π)+((re(acos(13+223(123i2)3233(123i2)))+2πiim(acos(13+223(123i2)3233(123i2))))+(re(acos(13233(12+3i2)+223(12+3i2)3))+2πiim(acos(13233(12+3i2)+223(12+3i2)3))))))+(re(acos(13+223(123i2)3233(123i2)))+iim(acos(13+223(123i2)3233(123i2)))))\operatorname{acos}{\left(- \frac{\sqrt[3]{2}}{3} + \frac{1}{3} + \frac{2^{\frac{2}{3}}}{3} \right)} + \left(\left(\left(\operatorname{re}{\left(\operatorname{acos}{\left(\frac{1}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)}{3} \right)}\right)} + i \operatorname{im}{\left(\operatorname{acos}{\left(\frac{1}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)}{3} \right)}\right)}\right) + \left(\left(- \operatorname{acos}{\left(- \frac{\sqrt[3]{2}}{3} + \frac{1}{3} + \frac{2^{\frac{2}{3}}}{3} \right)} + 2 \pi\right) + \left(\left(- \operatorname{re}{\left(\operatorname{acos}{\left(\frac{1}{3} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)} \right)}\right)} + 2 \pi - i \operatorname{im}{\left(\operatorname{acos}{\left(\frac{1}{3} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)} \right)}\right)}\right) + \left(- \operatorname{re}{\left(\operatorname{acos}{\left(\frac{1}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)}{3} \right)}\right)} + 2 \pi - i \operatorname{im}{\left(\operatorname{acos}{\left(\frac{1}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)}{3} \right)}\right)}\right)\right)\right)\right) + \left(\operatorname{re}{\left(\operatorname{acos}{\left(\frac{1}{3} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)} \right)}\right)} + i \operatorname{im}{\left(\operatorname{acos}{\left(\frac{1}{3} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)} \right)}\right)}\right)\right)
    =
    6*pi
    6π6 \pi
    произведение
    /    /    /                             /          ___\\\              /    /                             /          ___\\\\ /    /    /                             /          ___\\\              /    /                             /          ___\\\\                                   /    /    /                             /          ___\\\     /    /                             /          ___\\\\ /    /    /                             /          ___\\\     /    /                             /          ___\\\\                       
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    |- re|acos|- - ----------------- + --------------------|| + 2*pi - I*im|acos|- - ----------------- + --------------------|||*|- re|acos|- - ----------------- + --------------------|| + 2*pi - I*im|acos|- - ----------------- + --------------------|||*|- acos|- - ----- + ----| + 2*pi|*|I*im|acos|- - ----------------- + --------------------|| + re|acos|- - ----------------- + --------------------|||*|I*im|acos|- - ----------------- + --------------------|| + re|acos|- - ----------------- + --------------------|||*acos|- - ----- + ----|
    |    |    |3     /          ___\            3          ||              |    |3     /          ___\            3          ||| |    |    |3     /          ___\            3          ||              |    |3     /          ___\            3          ||| \      \3     3      3  /       / |    |    |3     /          ___\            3          ||     |    |3     /          ___\            3          ||| |    |    |3     /          ___\            3          ||     |    |3     /          ___\            3          |||     \3     3      3  /
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    \    \    \      \  2      2   /                       //              \    \      \  2      2   /                       /// \    \    \      \  2      2   /                       //              \    \      \  2      2   /                       ///                                   \    \    \      \  2      2   /                       //     \    \      \  2      2   /                       /// \    \    \      \  2      2   /                       //     \    \      \  2      2   /                       ///                       
    (re(acos(13233(12+3i2)+223(12+3i2)3))+2πiim(acos(13233(12+3i2)+223(12+3i2)3)))(re(acos(13+223(123i2)3233(123i2)))+2πiim(acos(13+223(123i2)3233(123i2))))(acos(233+13+2233)+2π)(re(acos(13233(12+3i2)+223(12+3i2)3))+iim(acos(13233(12+3i2)+223(12+3i2)3)))(re(acos(13+223(123i2)3233(123i2)))+iim(acos(13+223(123i2)3233(123i2))))acos(233+13+2233)\left(- \operatorname{re}{\left(\operatorname{acos}{\left(\frac{1}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)}{3} \right)}\right)} + 2 \pi - i \operatorname{im}{\left(\operatorname{acos}{\left(\frac{1}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)}{3} \right)}\right)}\right) \left(- \operatorname{re}{\left(\operatorname{acos}{\left(\frac{1}{3} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)} \right)}\right)} + 2 \pi - i \operatorname{im}{\left(\operatorname{acos}{\left(\frac{1}{3} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)} \right)}\right)}\right) \left(- \operatorname{acos}{\left(- \frac{\sqrt[3]{2}}{3} + \frac{1}{3} + \frac{2^{\frac{2}{3}}}{3} \right)} + 2 \pi\right) \left(\operatorname{re}{\left(\operatorname{acos}{\left(\frac{1}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)}{3} \right)}\right)} + i \operatorname{im}{\left(\operatorname{acos}{\left(\frac{1}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} + \frac{\sqrt{3} i}{2}\right)}{3} \right)}\right)}\right) \left(\operatorname{re}{\left(\operatorname{acos}{\left(\frac{1}{3} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)} \right)}\right)} + i \operatorname{im}{\left(\operatorname{acos}{\left(\frac{1}{3} + \frac{2^{\frac{2}{3}} \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)}{3} - \frac{\sqrt[3]{2}}{3 \left(- \frac{1}{2} - \frac{\sqrt{3} i}{2}\right)} \right)}\right)}\right) \operatorname{acos}{\left(- \frac{\sqrt[3]{2}}{3} + \frac{1}{3} + \frac{2^{\frac{2}{3}}}{3} \right)}
    =
    /      /    3 ___    2/3\       \ /    /    /     2/3   3 ___     3 ___   ___      2/3   ___\\     /    /     2/3   3 ___     3 ___   ___      2/3   ___\\\ /    /    /     2/3   3 ___     3 ___   ___      2/3   ___\\     /    /     2/3   3 ___     3 ___   ___      2/3   ___\\\ /            /    /     2/3   3 ___     3 ___   ___      2/3   ___\\     /    /     2/3   3 ___     3 ___   ___      2/3   ___\\\ /            /    /     2/3   3 ___     3 ___   ___      2/3   ___\\     /    /     2/3   3 ___     3 ___   ___      2/3   ___\\\     /    3 ___    2/3\
    |      |1   \/ 2    2   |       | |    |    |1   2      \/ 2    I*\/ 2 *\/ 3    I*2   *\/ 3 ||     |    |1   2      \/ 2    I*\/ 2 *\/ 3    I*2   *\/ 3 ||| |    |    |1   2      \/ 2    I*\/ 2 *\/ 3    I*2   *\/ 3 ||     |    |1   2      \/ 2    I*\/ 2 *\/ 3    I*2   *\/ 3 ||| |            |    |1   2      \/ 2    I*\/ 2 *\/ 3    I*2   *\/ 3 ||     |    |1   2      \/ 2    I*\/ 2 *\/ 3    I*2   *\/ 3 ||| |            |    |1   2      \/ 2    I*\/ 2 *\/ 3    I*2   *\/ 3 ||     |    |1   2      \/ 2    I*\/ 2 *\/ 3    I*2   *\/ 3 |||     |1   \/ 2    2   |
    |- acos|- - ----- + ----| + 2*pi|*|I*im|acos|- - ---- + ----- - ------------- - ------------|| + re|acos|- - ---- + ----- - ------------- - ------------|||*|I*im|acos|- - ---- + ----- + ------------- + ------------|| + re|acos|- - ---- + ----- + ------------- + ------------|||*|-2*pi + I*im|acos|- - ---- + ----- - ------------- - ------------|| + re|acos|- - ---- + ----- - ------------- - ------------|||*|-2*pi + I*im|acos|- - ---- + ----- + ------------- + ------------|| + re|acos|- - ---- + ----- + ------------- + ------------|||*acos|- - ----- + ----|
    \      \3     3      3  /       / \    \    \3    6       6           6              6      //     \    \3    6       6           6              6      /// \    \    \3    6       6           6              6      //     \    \3    6       6           6              6      /// \            \    \3    6       6           6              6      //     \    \3    6       6           6              6      /// \            \    \3    6       6           6              6      //     \    \3    6       6           6              6      ///     \3     3      3  /
    (re(acos(2236+236+13+233i6+2233i6))+iim(acos(2236+236+13+233i6+2233i6)))(re(acos(2236+236+132233i6233i6))+iim(acos(2236+236+132233i6233i6)))(acos(233+13+2233)+2π)(2π+re(acos(2236+236+13+233i6+2233i6))+iim(acos(2236+236+13+233i6+2233i6)))(2π+re(acos(2236+236+132233i6233i6))+iim(acos(2236+236+132233i6233i6)))acos(233+13+2233)\left(\operatorname{re}{\left(\operatorname{acos}{\left(- \frac{2^{\frac{2}{3}}}{6} + \frac{\sqrt[3]{2}}{6} + \frac{1}{3} + \frac{\sqrt[3]{2} \sqrt{3} i}{6} + \frac{2^{\frac{2}{3}} \sqrt{3} i}{6} \right)}\right)} + i \operatorname{im}{\left(\operatorname{acos}{\left(- \frac{2^{\frac{2}{3}}}{6} + \frac{\sqrt[3]{2}}{6} + \frac{1}{3} + \frac{\sqrt[3]{2} \sqrt{3} i}{6} + \frac{2^{\frac{2}{3}} \sqrt{3} i}{6} \right)}\right)}\right) \left(\operatorname{re}{\left(\operatorname{acos}{\left(- \frac{2^{\frac{2}{3}}}{6} + \frac{\sqrt[3]{2}}{6} + \frac{1}{3} - \frac{2^{\frac{2}{3}} \sqrt{3} i}{6} - \frac{\sqrt[3]{2} \sqrt{3} i}{6} \right)}\right)} + i \operatorname{im}{\left(\operatorname{acos}{\left(- \frac{2^{\frac{2}{3}}}{6} + \frac{\sqrt[3]{2}}{6} + \frac{1}{3} - \frac{2^{\frac{2}{3}} \sqrt{3} i}{6} - \frac{\sqrt[3]{2} \sqrt{3} i}{6} \right)}\right)}\right) \left(- \operatorname{acos}{\left(- \frac{\sqrt[3]{2}}{3} + \frac{1}{3} + \frac{2^{\frac{2}{3}}}{3} \right)} + 2 \pi\right) \left(- 2 \pi + \operatorname{re}{\left(\operatorname{acos}{\left(- \frac{2^{\frac{2}{3}}}{6} + \frac{\sqrt[3]{2}}{6} + \frac{1}{3} + \frac{\sqrt[3]{2} \sqrt{3} i}{6} + \frac{2^{\frac{2}{3}} \sqrt{3} i}{6} \right)}\right)} + i \operatorname{im}{\left(\operatorname{acos}{\left(- \frac{2^{\frac{2}{3}}}{6} + \frac{\sqrt[3]{2}}{6} + \frac{1}{3} + \frac{\sqrt[3]{2} \sqrt{3} i}{6} + \frac{2^{\frac{2}{3}} \sqrt{3} i}{6} \right)}\right)}\right) \left(- 2 \pi + \operatorname{re}{\left(\operatorname{acos}{\left(- \frac{2^{\frac{2}{3}}}{6} + \frac{\sqrt[3]{2}}{6} + \frac{1}{3} - \frac{2^{\frac{2}{3}} \sqrt{3} i}{6} - \frac{\sqrt[3]{2} \sqrt{3} i}{6} \right)}\right)} + i \operatorname{im}{\left(\operatorname{acos}{\left(- \frac{2^{\frac{2}{3}}}{6} + \frac{\sqrt[3]{2}}{6} + \frac{1}{3} - \frac{2^{\frac{2}{3}} \sqrt{3} i}{6} - \frac{\sqrt[3]{2} \sqrt{3} i}{6} \right)}\right)}\right) \operatorname{acos}{\left(- \frac{\sqrt[3]{2}}{3} + \frac{1}{3} + \frac{2^{\frac{2}{3}}}{3} \right)}