F.4 polynomials

1.if x+2 is a factor of x^3 - ax^2 +2b then -2a + b -1=?
ANS:3

2.if x^2 -9 is a factor o 2x^3 +ax -18x +7b , find a pair of possible values of
a and b
ANS:a=7 b=-9

3.P(x)=ax^5 - bx^3 + cx + d is divided dy x+2 , the remainder is R
if P(x) is divided by x-2 remainder is ?
ANS:2d-R

4.P(x) is divided dy x-a the remainder is R
IF P(x)- 2R is divided by x-a remainder is ?
ANS : -R

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