# Math

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x^4-4x^3+3x^2+8x-16

Find the zeroes given one is x^2-x-4.

I don't know what to do now. i tried synthetic division. pls help : D

• Math -

Synthetic division is usually only done with linear divisors, for quadratic divisors use long algebraic division. That gave me ....

(x^4-4x^3+3x^2+8x-16)/(x^2 - x - 4)
= x^2 - 3x + 4

so solving x^2 - 3x + 4 = 0
x = (3 ± √-7)/2
= (3 ± i√7)/2

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