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Single Variable Calculus
Differentiation
01The Derivative as the Slope of the Tangent Line02Secant Lines and the Limit Definition of the Derivative03Differentiating 1/x Straight From the Definition04Tangents to 1/x and the Triangle of Area 205Newton and Leibniz Notation, and the Power RuleProblem set0/10Problem set 20/10MIT problem set0/3Practice∞
01The Derivative as an Instantaneous Rate of Change02Rates of Change Without Time: Gradient and Sensitivity03Easy Limits, 0/0, and One-Sided Limits04Continuity, Jumps, and Removable Discontinuities05Infinite Discontinuities: 1/x and Its Derivative06Differentiable Implies ContinuousProblem set0/10Problem set 20/10Practice∞
01Two Kinds of Formula, and the Derivative of Sine02The Derivative of Cosine, and Two Limits at Zero03Bow and Bowstring: Proving the Two Trig Limits04Why the Trig Derivatives Hold Only in Radians05A Geometric Proof: Sine as a Height on the Circle06Finishing the Proof, and the Product and Quotient RulesProblem set0/10Problem set 20/10MIT problem set0/1Practice∞
01Proving the Product Rule: Change One Factor at a Time02The Quotient Rule, and the Power Rule for Negative Exponents03The Chain Rule: Differentiating a Function of a Function04Higher Derivatives: The Sine Cycle and Three Notations05The nth Derivative of xⁿ Is n Factorial, by InductionProblem set0/10Problem set 20/10MIT problem set0/2Practice∞
01The Power Rule for Rational Exponents02The Slope of a Circle, Two Ways03Implicit Differentiation of a Quartic Curve04Inverse Functions and the Reflection Across y = x05Derivatives of the Arctangent and ArcsineProblem set0/10Problem set 20/10MIT problem set0/1Practice∞

Inverse Functions and the Reflection Across y = x

Why is the graph of an inverse the original reflected across y = x, and what turns the tangent curve into an arctangent that levels off?


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    1. 1

      The inverse g=f−1g = f^{-1}g=f−1 and g(f(x))=xg(f(x)) = xg(f(x))=x

      Write the definition: a one-to-one fff makes g(y)=xg(y) = xg(y)=x a function with g(f(x))=xg(f(x)) = xg(f(x))=x, and carry f(x)=xf(x) = \sqrt{x}f(x)=x​ through to g(y)=y2g(y) = y^2g(y)=y2.

    2. 2

      The inverse graph as a reflection in the diagonal

      Record that graphing the inverse on the same axes trades each point (x,y)(x, y)(x,y) for (y,x)(y, x)(y,x), a reflection in the diagonal, and draw x\sqrt{x}x​ against x2x^2x2, x≥0x \ge 0x≥0.

    3. 3

      The arctangent graph and its asymptotes

      State that y=arctan⁡xy = \arctan xy=arctanx means tan⁡y=x\tan y = xtany=x, reflect the tangent on (−π/2,π/2)(-\pi/2, \pi/2)(−π/2,π/2), and record the horizontal asymptotes y=±π/2y = \pm\pi/2y=±π/2 with the limits at ±∞\pm\infty±∞.

    Attempt 1 of 2