Question

If( x+2) is the factor of x³-ax²-bx+4 then the value of (b-2a) is​

Answer 1

Answer:

since,x+2 is a factor of a polynomial p(x) =x³-ax²-bx+4

so,p(-2)=0

(-2)³-a(-2)²-b(-2)+4=0

-8-4a+2b+4=0

-4-4a+2b=0

2(-2-2a+b)=0

-2-2a+b=0

b-2a=2