Question

if the polynomial 3x²+kx²+2x-3 leaves a remainder 5, find the value of k. Is x+1 a factor of this polynomial​

Answer 1

Let f(x)=2x

3

+3x

2

−kx+5

By remainder theorem, when f(x) is divided by (x−2)

x−2=0,⇒x=2

the remainder =f(2)

=2(2)

3

+3(2)

2

−k(2)+5

=16+12−2k+5

=33−2k

According to question

33−2k=7

⇒2k=26

⇒k=13