find the values of a and b,if  x square-4 is a factor of ax raise to 4+2x raise to 3-3x square+bx-4

x2-4

x2-22

(x+2)(x-2)

Let p(x)=ax4+2x3-3x2+bx-4

(x+2) and (x-2) are the factors of p(x)

p(-2)=0

a(-2)4+2(-2)3-3(-2)2+b(-2)-4

=0

16a-16-12-2b-4=0

16a-2b-32=0 ..(1)

p(2)=0

a(2)4+2(2)3-3(2)2+b(2)-4

=0

16a+16-12+2b-4=0

16a+2b=0 ..(2)

Equating 1 and 2

16a-2b-32=16a+2b

-4b=32

b=-8

From 2

16a+2b=0

16a-16=0

a=16/16

a=1

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