Question

What js f(5) for the function -2x²+2x-3

A. -107
B.-63
C. -43
D. -37

Answer 1

The given function is in terms of x.

So the function is f(x)=
`-2x^(2)+2x-3`

Find f(5), that means the value of x is 5

so plug in x =5 in the given function f(x),

f(x) =
`-2x^(2)+2x-3`

f(5) =
`-2(5)^(2)+2(5)-3`

f(5) = -2(5)(5) + 2(5) -3

f(5) = -2(25) + 10 -3

f(5) = -50 + 10 -3 (apply the rule of integers)

f(5) = -40 -3

f(5) = -43

Answer is option C.

Answer 2

The given function in terms of x is
`f(x)=-2x^(2)+2x-3`

We have to calculate f(5), it means in the given function we have to substitute the value of x as 5.

`f(5)=(-2 *5^(2))+(2 * 5)-3`

`f(5)=-50+10-3`

f(5) = -40-3

f(5) = -43.

So, the value of f(5) is -43.

So, option C is the correct answer.