Question

-20x^4-10x
with explanation pls ....
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Answer 1

Step-by-step explanation:

Given equation, x

4

−10x

2

−20x−16=0

Consider f(x)=x

4

−10x

2

−20x−16

By inspection we can easily see that f(−2)=0. Therefore, (x+2) is a factor of the given equation

∴f(x)=(x+2)⋅g(x)⟹g(x)=x

3

−2x

2

−6x−8

We need to find root of g(x)=0

⟹x

3

–2x

2

−6x−8=0⟹x

3

+2x

2

+2x−4x

2

−8x−8=0⟹(x−4)(x

2

+2x+2)=0

Solving the quadratic we have, x=−1±i

∴ the roots of the given equation are x=−2,4,−1±i