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## #1 2013-04-17 17:20:47

mel179
Guest

### Solving cubic equation

[math]Hi there!

I forgot most of my math from school and uni and now I want to calculate the mesh size of a porous gel.
I came up with this equation:

x^3 = 0.8 (a+x)^3

I measured all values for a using nanoindentation so I need to solve this equation for x.
Could anybody help please?

Thanks a lot

## #2 2013-04-17 17:28:49

bob bundy
Moderator

Offline

### Re: Solving cubic equation

hi mel179

Welcome to the forum.

Cube root both sides

note: cube root of 0.8 is approximately 0.9283.
On a calculator press the y^x button (some calcs show incorrectly as x^y) with (1/3) as the y value.
ie. 0.8 y^x (1/3)

Hope that's what you need.

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #3 2013-04-18 01:26:09

mel179
Guest

### Re: Solving cubic equation

Wow! I didn't expect it to be so easy, that's embarrassing for me.

Thank you so much!!!! You made my day

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