Answers for FP1 homework for 17/11/15 on solving cubic equations

1. Roots of z3−5z2+8z−6=0 are 1+i, 1−i, 3

2. Roots of z3−2z2+z−2=0 are i, −i, 2

3. Roots of z3−2z+4=0 are 1+i, 1−i, −2

4. Roots of z3−8=0 are 2 cis (2π/3), 2 cis (−2π/3), 2

5. Roots of z3−3z2+7z−5=0 are 1+2i, 1−2i, 1

6. Roots of z3−6z2+13z=0 are 3+2i, 3−2i, 0

7. Roots of z3−9z2+31z−39=0 are 3−2i, 3+2i, 3

8. Roots of z3−10z2+37z−52=0 are 3−2i, 3+2i, 4

9. Roots of z3−27=0 are 3 cis (2π/3), 3 cis (−2π/3), 3