Gradient method on matlab for estimating a,b?

I have x\dot=-ax+b*cost

and i want to estimate a,b with gradient method how can i do that please help me!!

[Star Strider]

Does the ‘\’ on the left hand side of your equation indicate a matrix left division (mldivide) or is it a typographical error?

Please clarify what variables represent your data, and what you want to do.

[Image Analyst]

Perhaps it was supposed to be an overdot https://en.wikipedia.org/wiki/Dot_%28diacritic%29 which is supposed to put a small dot above the x, which typically means a time derivative.

[Star Strider]

I didn’t consider that it could be an overdot.

Next question:

1. Is ‘x’ a function of time or of ‘cost’?
2. Is ‘cost’ a constant or a function of time?