find the indicated function value f(x)=2x^2-4x-4, g(x)=4x-7 Fing (f+g)(3)

Question

I need help solving this problem please

Answer 1

Hi Lisa,

 

Let's begin by understanding what is meant by the notation:  (f + g)(3).

 

This is equivalent to saying f(3) + g(3).

 

So what we need to do is substitute the value of 3 for where ever we see an X in each of these functions and then numerically evaluate each function and sum the results.

 

Let's begin by evaluating f(x) using the value of 3:

    f(x) = 2x² - 4x - 4 (original function)

    f(3) = 2(3)² - 4(3) - 4 (plugging in 3 for x)

    f(3) = 2 (computed result)

 

Now let's evaluate g(x) using the value of 3:

    g(x) = 4x - 7 (original function)

    g(x) = 4(3) - 7 (plugging in 3 for x)

    g(x) = 5 (computed result)

 

Finally, we'll sum our results:

    (f + g)(3) = 2 + 3 (add f(3) and g(3))

    (f + g)(3) = 5 (final answer)

      

Thanks for submitting this problem and glad to have been of help.

 

Regards, Jordan.