Find the derivative using the delta process.

f(x) = kx + c

MY WORK:

f'(x) = lim as h--->0 for kx + c

f'(x) = lim as --->0 f(x + h) - f(x)/h

f'(x) = lim as --->0 k(kx + c + h) - kx + c

f'(x) = lim as --->0 kx + kc + kh - kx + c

This is where I get stuck.

The answer is simply k but how do I find the answer using the delta process?