Ok, I decided to review basic algebra since I haven't done anything with it in like, forever. I came across an inverse function problem that I can't get the right answer.(adsbygoogle = window.adsbygoogle || []).push({});

the equation is:

y = cuberoot(x+sqrt(1+x^2)) + cuberoot(x-sqrt(1+x^2))

I tried replacing X with Y, and solving for Y

and getting rid of the cube roots by cubing both sides

X^3 = y + sqrt(1+y^2) + y - sqrt(1+y^2)

simplifying a bit (the square roots go away)

x^3 = 2y

so

y = (1/2)x^3

Yet the book I'm using says the answer is y=(1/2)(3x+x^3)

What did I do wrong?

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# Homework Help: Inverse function help

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