Question

Find g[f(4)] if f(x) = 5x and g(x) = 3x - 7.

Answer 1

The value of g[f(4)] was found to be 53.

Solution-

Given in the question,

`f(x)=5x,\ g(x)=3x-7`

As we have to find the value of composite function, so putting f(x) in g(x),

`g[f(x)]=3(5x)-7=15x-7`

Now putting x = 4,

`g[f(4)]=15(4)-7= 60-7 = 53`

Therefore, the value of g[f(4)] was found to be 53.