Find the values of k and p so that the expression -2x^3-kx^2+7x+p2x3kx2+7x+p can be divided by 2x^2+5x+32x2+5x+3 without leavng any remainder.?

1 Answer
Jul 13, 2016

{k = 1, p = 6}{k=1,p=6}

Explanation:

Calling

f(x) = -2 x^3 - k x^2 + 7 x + pf(x)=2x3kx2+7x+p and
g(x) = 2 x^2 + 5 x + 3 g(x)=2x2+5x+3

we need k,pk,p such that for suitable b,cb,c

f(x)=g(x)(b x+c)f(x)=g(x)(bx+c)

Equating coefficients we have the conditions

{ (-3 c + p =0), ( 7 - 3 b - 5 c = 0), (5 + 2 c + k = 0), (2+2b=0) :}

Solving we have

{b = -1, c = 2, k = 1, p = 6}

so

{k = 1, p = 6}