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Help with functions question please

The function is defined as f(X)=3+√x
It then says evaluate ff(169) for part A and then Find an expression for f-1(x) in terms of X for part B.
Could anyone possibly help with this please??

Reply 1

bluemadhatter

hmmm im guessing a would be f(3+√x) = 3+√x so ff(x) = 3+√3+√x = 169 and then maybe try to solve it?

not sure about b

Reply 2

davros

Original post by frances98

The function is defined as f(X)=3+√x
It then says evaluate ff(169) for part A and then Find an expression for f-1(x) in terms of X for part B.
Could anyone possibly help with this please??

For part A, can you work out f(169)? Call this result y. Now can you work out f(y)?