Question

TASK 1

Answer 1

Remember that if f and g are inverses of one another, then

f(g(x)) = g(f(x)) = x

1/2. Take a = 0 and b = 1 (or any non-zero number) so that

f(x) = x + 0/1   ⇒   f(x) = x

If g is to be an inverse of f, we need

g(f(x)) = g(x) = x

so that c = 1 and d = 0.

3. With f(x) = x + a/b and g(x) = cx - d, we have

g(f(x)) = g(x + a/b) = c (x + a/b) - d = cx + ac/b - d

and of course, with a,b,c,d as before, we get g(f(x)) = x.

4. This would be a very uninteresting graph for the example I've cooked up here, just containing the line y = x...