Question

if x³+2x²+ax+b has factors X+1 and x-1 find and b​

Answer 1

Answer:

x+1=0. x-1=0

x = -1. x =1

(-1)³+2(-1)²+a(-1)+b=(1)³+2(1)²+a(1)+b

-1-a=1+a. (b & 2 is subtracted in both side)

-1-1=a+a

2a = -2

a= -1

x³+2x²+ax+b=(1)³+2(1)²+-1(1)+b=0

=> 2+b=0

=> b= -2