If f(x)=sqrt(x+3)f(x)=x+3 and g(x)=8x-7g(x)=8x7, what is f(g(x))f(g(x))?

1 Answer
Nov 8, 2016

f(g(x))=2sqrt(2x-1)f(g(x))=22x1

Explanation:

To evaluate f(g(x)), substitute the value of g(x) for x in f(x).

rArrf(g(x))=f(color(red)(8x-7))=sqrt(color(red)(8x-7)+3)=sqrt(8x-4f(g(x))=f(8x7)=8x7+3=8x4

color(orange)"Reminder " color(red)(bar(ul(|color(white)(2/2)color(black)(sqrtaxxsqrtbhArrsqrt(ab))color(white)(2/2)|)))

rArrsqrt(8x-4)=sqrt(4(2x-1))=sqrt4xxsqrt(2x-1)

=2sqrt(2x-1)