Question

Find The value of a and b, if x^2-1 is a Factor of x^4 + x^3 + 8x^2 + ax + b.

Answer 1

Hey Friends,
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Let f(x) be x^4 + x^3 +8x^2 +ax + b
If x^2-1 is a factor of f(x) Then, f(x)=f(1)
So, f(1)=1^4+1^3+8×1^2+a+b
=1+1+8+a+b
=10+a+b=0
=a+b=0

Hope it's help you!!!!
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