(adsbygoogle = window.adsbygoogle || []).push({}); One to one functions/range --calc II

In calc II, we are learning about inverse functions, So I have two questions:

1. Is there any way to find out if a function is one to one without looking at the graph?

2. How can I determine the range of a function based on the equation alone (without referring to the graph)?

-Lastly, there is this example on the book that says f(x) = 1/4x^3+x-1 and asks "what is f^-1(x) when x= 3?" The explanation just says that f(x)=3 when x=2 so f^-1(3)=2. But how did they find f(2)=3?? I tried doing that but came accross 3 solutions--is looking at the graph necessary to know this?

Thank you.

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# Homework Help: One to one functions/range -calc II

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