Inverse challenge

So, my teacher have given me this practice problem for homework. And I had tried my best to solve it but at the end clueless. I asked my friends, how to solve the question but he too is also confuse. It would be great if you can help me to solve this challenges.

Easy Math Editor

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
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Comments

Hints:

a. $f(f^{-1}(x)) = x.$

b. Write the right hand side as an improper fraction. If $f(x)$ equals that fraction for every real number in the domain, then what must be true of the coefficients in the numerator?

Steven Yuan - 3 years, 4 months ago

Ask Siri

Annie Li - 3 years, 4 months ago

lol

A Former Brilliant Member - 3 years, 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$