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Differential Calculus2D

The Derivative - Theory & Concepts - Secant Tangent

Master the core of differential calculus: the historical context, one-sided derivatives, differentiability, differentiation rules, and implicit differentiation.

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Secant Line to Tangent Line

Adjust the distance h between the two points. As h → 0, the secant line (connecting two points) converges into the tangent line (touching one point), demonstrating the fundamental definition of the derivative. The curve is f(x) = x²/4 + 1.

Calculations:
Point 1: (x, f(x)) = (1, 1.25)
Point 2: (x+h, f(x+h)) = (3.00, 3.25)
Secant Slope: [f(x+h) - f(x)] / h = 1.000
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