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# C3 Question about functions watch

1. The function f(x) is defined by {x∈R, x > 0}

a) Find in similar terms. (x) = √x + 3

b) Sketch. Done.

c) Find values of x such that

Why in the example does it say

When

f(x) = x

Why is the same as x?

Thank you for your help.
2. Think where they reflect.
3. If you draw both equations on the graph, you see that f(x) intercepts f-1(x) on the line y=x, hence f(x) = x
4. (Original post by *MJ*)
Think where they reflect.
y = x

I get itttt.

(Original post by Kameo)
If you draw both equations on the graph, you see that f(x) intercepts f-1(x) on the line y=x, hence f(x) = x
Would this always be the case if I was asked to find values of x such that even if the function f(x) is different?

Thank you!!

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