2 d*a *(153*d + 10*a*(d + 2*a)) ----------------------------- 2
/ ___ ________________\ / ___ ________________\ | d \/ 5 *\/ d*(-612 + 5*d) | | d \/ 5 *\/ d*(-612 + 5*d) | a*|a + - + ------------------------|*|a + - - ------------------------|*d \ 4 20 / \ 4 20 /
/ 2\ 2 | 3 153*a | 4 d *|5*a + ------| + 10*d*a \ 2 /
2 2 3 2 4 153*a *d 5*a *d + 10*d*a + --------- 2