,

Set up the composite result function.

Evaluate by substituting in the value of into .

Combine and .

Move the negative in front of the fraction.

Write as a fraction with a common denominator.

Combine the numerators over the common denominator.

Multiply the numerator by the reciprocal of the denominator.

Combine and .

Find f(g(x)) f(x)=7/(1-3x) , g(x)=1/x