anyone with some more up to date maths skills ? 25 years back, no probs, not anymore. Trying to re look at the input of a non linear multiple regression

y=c+a1*z1+a2*z1^2+a3*z1^3+b1*z2+b2*z2^2+b3*z2^3

Looking to transpose the formula to z2=.......................

can't do it anymore

First step is to solve for (b₁ * z₂²⁾ + (b₃ * z₂³), to isolate z₂

y - (all the rest) = (b₁ * z₂²⁾ + (b₃ * z₂³)

Too many Hong Thiongs at this point.

I tried to figure it out for you, but my calculator only has digits, no b's and z's on that bloody thing.

This help?

http://www.quickmath.com/webMathematica3/quickmath/equations/solve/basic.jsp#c=solve_stepssolveequation&v1=y%3Dc%2Ba1*z1%2Ba2*z1%5E2%2Ba3*z1%5E3%2Bb1*z2%2Bb2*z2%5E2%2Bb3*z2%5E3&v2=z2

This help?

http://www.quickmath.com/webMathematica3/quickmath/equations/solve/basic.jsp#c=solve_stepssolveequation&v1=y%3Dc%2Ba1*z1%2Ba2*z1%5E2%2Ba3*z1%5E3%2Bb1*z2%2Bb2*z2%5E2%2Bb3*z2%5E3&v2=z2

That makes more sense.

I got it z^2 = zzzzzzzzzzzzzzz

Let me get back to you tomorrow

tell me what * and ^ are supposed to mean, and I'll tell you. I'm very old school. Think clay tablets and Roman numerals.

Solve for X..jpeg

Oh what a headache. I can't do it. I can't get anything z^2.

I'm getting an end answer of 0 so I'm going back to bed.

Is this a trick question?

Lol

Not a trick question. I am using multi variable non linear regression analysis to look at two inputs with relation to a known output.

I dug up a really cool spreadsheet which did the regression to the power of three.

result is a get a really cool regression line

Now I'm trying to use that to look back at original data to see whether it's underperforming or over performing

Using it for a real life application, Not a school project

Sent from my iPhone using Thaivisa Connect Thailand mobile app

Ask Admin Tywais, he should be able to solve it.

Don't bother with us High school drop outs

Sent from my iPad so Please excuse any typos

The answer is zero.

OP, you Sir are off your whatever. You have 8 unknowns in 1 equation, A1, A2, A3, B1,B2, B3 plus Z1 and Z2. Please let me know, when you get out of the loony bin, and we can go for a few beers. Good Luck

Not Thai related

Closed