Question

Let f(x)= x+3 and g(x)= 4x-3. Find (f+g)(3).

Answer 1

(f + g)(3) = f(3) + g(3).

Find f(3).

f(3) = x + 3

f(3) = 3 + 3

f(3) = 6

Now find g(3).

g(3) = 4x - 3

g(3) = 4(3) - 3

g(3) = 12 - 3

g(3) = 9

We finally add f(3) + g(3).

f(3) + g(3) = 6 + 9

f(3) + g(3) = 15

The answer is 15.