Given: f(x)=(x+3)/7 Put y for f(x):
y=(x+3)/7 Solve the equation for x, getting the invers of f(x)
x=7y-3 Put f¯¹(x) for x. We have:
f¯¹(y)=7y-3 Substitute x for y. We have:
f¯¹(x)=7x-3
CK: The graphs of f(x) and f¯¹(x) are symmetric with respect to the line y=x, so f(f¯¹(x))=x.
f(f¯¹(x))=f(7x-3)={(7x-3)+3}/7=7x/7=x CKD.
Therefore, the answer is: f¯¹(x)=7x-3