Need a strategy for inverting a function

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To invert the function x = -K1 * y * √(K2 - y), the discussion suggests squaring both sides to obtain a cubic equation in y. The solution y = 0 is identified as one evident root, leading to a simpler quadratic to solve. Participants reference a resource for solving cubic equations and clarify that only the first solution avoids imaginary numbers. The conversation emphasizes the importance of understanding cubic equations and their roots for effective problem-solving.
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I can't solve for y from:

x = - K_{1}* y *\sqrt{K_{2}-y}

where K(1) and K(2) are constants.

I am pretty sure as a younger man I was taught how to do this but I can't remember the strategies I can/should use. Any thougths would be very appreciated.
 
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Square both sides and you get a cubic in y, out of which the solution y=0 is evident, so you've only got a simple quadratic to solve.
 
Thanks, and genneth I'm not one to talk!

Shooting Star, It looks from the page you sent that the general form is:

y = 3f/[-e+(e3-27f2)1/3],
y = 3f/[-e+(e3-27f2)1/3(-1+sqrt[-3])/2],
y = 3f/[-e+(e3-27f2)1/3(-1-sqrt[-3])/2].

so only the first of these avoids i, right?
 

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