thank your for respond,

Actually i face non linearity in liner regression model and i used data transfer using Log and i believe problem solved using the Log was useful so far.

I agree with the Sofia Cividini

Lets say that you have the data (Xi,Yi) and you suppose that:

Yi=b0+b1 Xi + b2 Xi2 + b3 Xi3 + ... + bn+1 Xin + ei

Now you have the varibales 1, Xi ,  Xi2 , ... ,  Xin

so you have OLS with them and find easy the b0,b1,...,bn+1.

Yes, but it might not be simple linear regression again. It would be multiple linear regression