Question

Find all the zeros of each equation.

x5 – 3x4 – 15x3 – 45x2 – 16x + 48 = 0

A. 3, 4, i
B. 4, –4, i,–i
C. 3, 4, –4, i, –i
D. 3, –4, –i

Answer 1

can anyone help??

Answer 2

Do you know how to work with synthetic division?

Answer 3

without thinking C has to be the one because it has 5roots and plynomial has high degree 5

Answer 4

Some roots can be repeated.

Answer 5

I'm questioning that original equation. Please double-check that you input it correctly.

Answer 6

Thanks! I have one more problem i need help with!

Answer 7

2.
7x2 – 144 = –x4

A. 3, –3, 4i, 0
B. 3, 4i
C. 3, –3, 4i, –4i
D. –3, –4i

Answer 8

oh and no i don't understand synthetic division :/

Answer 9

I don't know how to teach you synthetic division in this forum. Way too much writing. I know the answer, but we're not allowed just to give a raw end-result answer. So, I'll give you 2 of the zeros which are 3 and -3. That leaves you with the factor x^2 + 16 = 0. You should be able to find the last 2 zeros from that. You can use the quadratic formula.

Answer 10

how do i use the quadratic formula to solve that though?

Answer 11

thank you so much for helping though!!

Answer 12

You are welcome!