SOLUTION: Find the remaining complex zeros of f(x) if -3 is a zero. f(x)=x^5 + x^4 - x^3 + 7x^2 - 20x + 12

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Find the remaining complex zeros of f(x) if -3 is a zero. f(x)=x^5 + x^4 - x^3 + 7x^2 - 20x + 12      Log On


   

Question 863068: Find the remaining complex zeros of f(x) if -3 is a zero.
f(x)=x^5 + x^4 - x^3 + 7x^2 - 20x + 12
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Not all of the remaining zeros are complex. Do synthetic division on the original 5th degree equation polynomial using -3 as a divisor. The result is:



The possible real roots of the quartic are .

Use synthetic division to find two more real roots. Hint: The two real roots are equal.

You will be left with a quadratic that you can solve using the quadratic formula for the conjugate pair of complex roots.

John

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