Question

F(x)=x^2-x+3 what is f(4)

Answer 1

f(4) = 15

Explanation:

Substitute 4 for x and solve for f(4).

`f(x)=x^2-x+3\\f(4)=(4)^2-4+3\\f(4)=16-4+3\\f(4)=15`

Answer 2

15

Explanation:

In the function f(x), x is the variable. So, whatever is in the parentheses, replacing x, should replace x throughout the entire function. So, to find f(4) simply plug in 4 for x.

• First, rewrite the function with 4 as x

f(4) = 4^2 - 4 + 3

• Next, combine like terms

f(4) = 4^2 - 1

• Then, raise 4 to the power of 2

f(4) = 16 - 1

• Finally, subtract

f(4) = 15