I don't understand how to do this problem, can you help me?
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Step-by-step explanation:
step 1. f(x) = rx + s
step 2. domain of f(x): all x
step 3. f'(x) = lim h->0 (f(x + h) - f(x))/h
step 4. f'(x) = lim h->0 (r(x + h) + s - (rx + s))/h
step 5. f'(x) = r
step 6. domain of f'(x): all x.