The teacher will be very surprised to see your correct solution 😉
________________ / ________________ \ 3 / _____ | ___ 3 / _____ ___ | 3 \/ 63 + 3*\/ 438 | \/ 3 *\/ 63 + 3*\/ 438 3*\/ 3 | x1 = 7 - --------------------- - ------------------- + I*|- ------------------------- + ---------------------| ________________ 2 | 2 ________________| 3 / _____ | 3 / _____ | 2*\/ 63 + 3*\/ 438 \ 2*\/ 63 + 3*\/ 438 /
________________ / ________________ \ 3 / _____ | ___ 3 / _____ ___ | 3 \/ 63 + 3*\/ 438 |\/ 3 *\/ 63 + 3*\/ 438 3*\/ 3 | x2 = 7 - --------------------- - ------------------- + I*|------------------------- - ---------------------| ________________ 2 | 2 ________________| 3 / _____ | 3 / _____ | 2*\/ 63 + 3*\/ 438 \ 2*\/ 63 + 3*\/ 438 /
________________ 3 / _____ 3 x3 = 7 + \/ 63 + 3*\/ 438 + ------------------- ________________ 3 / _____ \/ 63 + 3*\/ 438
x3 = 3/(3*sqrt(438) + 63)^(1/3) + (3*sqrt(438) + 63)^(1/3) + 7
sum
________________ / ________________ \ ________________ / ________________ \ 3 / _____ | ___ 3 / _____ ___ | 3 / _____ | ___ 3 / _____ ___ | ________________ 3 \/ 63 + 3*\/ 438 | \/ 3 *\/ 63 + 3*\/ 438 3*\/ 3 | 3 \/ 63 + 3*\/ 438 |\/ 3 *\/ 63 + 3*\/ 438 3*\/ 3 | 3 / _____ 3 7 - --------------------- - ------------------- + I*|- ------------------------- + ---------------------| + 7 - --------------------- - ------------------- + I*|------------------------- - ---------------------| + 7 + \/ 63 + 3*\/ 438 + ------------------- ________________ 2 | 2 ________________| ________________ 2 | 2 ________________| ________________ 3 / _____ | 3 / _____ | 3 / _____ | 3 / _____ | 3 / _____ 2*\/ 63 + 3*\/ 438 \ 2*\/ 63 + 3*\/ 438 / 2*\/ 63 + 3*\/ 438 \ 2*\/ 63 + 3*\/ 438 / \/ 63 + 3*\/ 438
=
/ ________________ \ / ________________ \ | ___ 3 / _____ ___ | | ___ 3 / _____ ___ | |\/ 3 *\/ 63 + 3*\/ 438 3*\/ 3 | | \/ 3 *\/ 63 + 3*\/ 438 3*\/ 3 | 21 + I*|------------------------- - ---------------------| + I*|- ------------------------- + ---------------------| | 2 ________________| | 2 ________________| | 3 / _____ | | 3 / _____ | \ 2*\/ 63 + 3*\/ 438 / \ 2*\/ 63 + 3*\/ 438 /
product
/ ________________ / ________________ \\ / ________________ / ________________ \\ | 3 / _____ | ___ 3 / _____ ___ || | 3 / _____ | ___ 3 / _____ ___ || / ________________ \ | 3 \/ 63 + 3*\/ 438 | \/ 3 *\/ 63 + 3*\/ 438 3*\/ 3 || | 3 \/ 63 + 3*\/ 438 |\/ 3 *\/ 63 + 3*\/ 438 3*\/ 3 || | 3 / _____ 3 | |7 - --------------------- - ------------------- + I*|- ------------------------- + ---------------------||*|7 - --------------------- - ------------------- + I*|------------------------- - ---------------------||*|7 + \/ 63 + 3*\/ 438 + -------------------| | ________________ 2 | 2 ________________|| | ________________ 2 | 2 ________________|| | ________________| | 3 / _____ | 3 / _____ || | 3 / _____ | 3 / _____ || | 3 / _____ | \ 2*\/ 63 + 3*\/ 438 \ 2*\/ 63 + 3*\/ 438 // \ 2*\/ 63 + 3*\/ 438 \ 2*\/ 63 + 3*\/ 438 // \ \/ 63 + 3*\/ 438 /
=
406
406
x1 = 4.19540092945257 + 3.82064495073103*i
x2 = 12.6091981410949
x3 = 4.19540092945257 - 3.82064495073103*i
x3 = 4.19540092945257 - 3.82064495073103*i