(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

If f(x)= x^3 +4x + 6,

a.) show f(x) is one to one.

b) Find inverse f(10)... f^-1(10) (hard to write type on a computer)

c) Find f^-1(10)'

2. Relevant equations

f^-1(x)' = 1/[f'(x)*f^-1(10)]

3. The attempt at a solution

a.) a function is monotonic when it is either always increasing or always decreasing. You can check by looking at the derivative, f(x)' = 3x^2 + 4. This Function is one to one because it is monotonic (always increasing).

b.) I simply cannot figure this out. I am pretty sure our professor does NOT want us to try to find a direct equation for f^-1(x). I believe she wants us to use the method she calls "inspection", to look at the problem carefully and figure out a y value, then f^-1(x) = y, so I can find f(10). pretty lost.

c.) See above... though I know the equation is f^-1(x)' = 1/[f'(x)*f^-1(10)]

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Inverse shminverse

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