Explain in one or two sentences why the slope of the secant line joining the points…

MATHEMATICS · Subjective · A Level · Mathematics · Differentiation · Differentiation

Problem

Explain in one or two sentences why the slope of the secant line joining the points

(a, f(a))

and

(a+h, f(a+h))

approaches the slope of the tangent to the curve

y=f(x)

x=a

h

tends to

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