Let f (x) be differentiable at x = 1 and f '(1) = 2, then [LIM (H → 0) f (1-h) - f (1)] / h is equal to

Let f (x) be differentiable at x = 1 and f '(1) = 2, then [LIM (H → 0) f (1-h) - f (1)] / h is equal to

lim(h→0) (f(1-h)-f(1))/h
=-lim (f(1-h)-f(1))/(-h)
According to the definition of derivative,
=-f'(1)
=-2
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