Function with 3 variables (I know how two are related )

[pangolo]

Homework Statement

I know that
k*u^3=F
And I have data of when you change Z , so for example if Z is 3, then u is 5 and F is 3.
And i need to get the function with only Z and F without u, how do I do it?

The Attempt at a Solution

I made a function through excel with Z and F but because U also varies I need to somehow substract it from the function?

 

[scottdave]

Is k a constant? Knowing F and u, you can calculate k. Then could you express u as a function of F?
How big is your data set? You could post it if not too big.

 

[CWatters]

Use the data points to calculate k.

The next step would be to write an equation that relates z and u an substitute to eliminate u in the equation you give. However I think you need more than one data point to write an equation relating z and u.