Question

Find the value of f (x)=2x³+7x+3 at x=-1​

Answer 1

Answer:

Let f(x)=2x

3

−kx

2

+7x−1.

Now according to the remainder theorem, when f(x) is divided by x−1 then the remainder is f(1).

Now, f(1)=2−k+7−1=8−k.

According to the problem,

8−k=3

or, k=5.