Question

If f(x)=4x2=1 and g(x)=x2-5, find (f-g)(x)
A:3x2+6
B:5x2-6
C:3x2-4
D:5x2-4

Answer 1

For this case we have the following functions:

`f (x) = 4x ^ 2 + 1\\g (x) = x ^ 2-5`

We must find
`(f-g) (x):`

By definition of operations with functions we have:

`(f-g) (x) = f (x) -g (x)`

So:

`(f-g) (x) = f (x) -g (x) = 4x ^ 2 + 1- (x ^ 2-5) = 4x ^ 2 + 1-x ^ 2 + 5 = 3x ^ 2 + 6`

Answer:

Option A

`3x ^ 2 + 6`