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一変数の微積分
微分
01微分係数とは何か:接線の傾きとして定義する02割線から接線へ:極限による微分係数の定義031/x の導関数:先に約分、極限はそのあと041/x の接線と、面積がいつも2になる三角形05微分の記法とべき関数の微分公式問題セット0/10問題セット20/10MIT 問題セット0/3
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 Continuous問題セット0/10問題セット20/10
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 Rules問題セット0/10問題セット20/10MIT 問題セット0/1
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 Induction問題セット0/10問題セット20/10MIT 問題セット0/2
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 Arcsine問題セット0/10問題セット20/10MIT 問題セット0/1
01The Derivative of aˣ and the Mystery Number M(a)02Defining e by Slope One, and the Derivative of ln x03M(a) = ln a: Differentiating aˣ and xˣ04Why (1 + 1/n)ⁿ Approaches e問題セット0/10問題セット20/10MIT 問題セット0/1
微分の応用
01Linear Approximation: A Curve Is Its Tangent Line02Five Linear Approximations at Zero03Combining Approximations, from Algebra to GPS Clocks04Quadratic Approximation: The Best-Fit Parabola問題セット0/10問題セット20/10MIT 問題セット0/1
01Linear Approximation as a Proportionality Rule02Quadratic Approximation: Why the ½, and Products03Curve Sketching: The Sign of f′ and Critical Points04Curve Sketching: Ends, Concavity and Inflection問題セット0/10問題セット20/10MIT 問題セット0/1
01Sketching Without Critical Points: (x+1)/(x+2)02A Five-Step Curve-Sketching Scheme, Applied to x / ln x03x / ln x: Inflection Point and Where Max and Min Can Occur問題セット0/10問題セット20/10
01Two Squares From One Wire: The Critical Point Gives the Least Area02The Open Box of Fixed Volume: Least Material When x = 2y03Related Rates: The Police Radar and the Conical Tank問題セット0/10問題セット20/10MIT 問題セット0/4
01The Hanging Ring: Why the String Makes Equal Angles02Newton's Method: Tangent Lines That Find the Square Root of Five03Why Newton's Method Doubles Its Digits, and How It Fails04The Mean Value Theorem: Somewhere You Hit Your Average Speed05Positive Derivative Means Increasing: Proving eˣ Exceeds 1 + x問題セット0/10問題セット20/10MIT 問題セット0/2
積分
01Differentials: dy = f′(x) dx and the Cube Root of 64.102Antiderivatives Differ Only by a Constant03Integration by Substitution and Advanced Guessing問題セット0/10問題セット20/10MIT 問題セット0/1
01Separation of Variables: dy/dx = −xy and the Bell Curve02General Solutions: Signs, Constants and Initial Conditions03Orthogonal Trajectories: Parabolas and Crossing Ellipses問題セット0/10問題セット20/10MIT 問題セット0/1
01The Definite Integral: Area as a Limit of Rectangle Sums02Area Under y = x²: Squeezing the Sum of Squares03Sigma Notation and the Area Pattern: b, b²/2, b³/304Riemann Sums: the Definite Integral and a Year of Loans問題セット0/10問題セット20/10MIT 問題セット0/1
01The Fundamental Theorem of Calculus: Area in One Line02Net Change and Signed Area: Integrating Velocity03Six Rules for Definite Integrals and Bounds on eᵇ04Substitution in Definite Integrals: Change the Limits問題セット0/10問題セット20/10MIT 問題セット0/1

このページは日本語版を準備中です

Derivatives of the Arctangent and Arcsine

How does one right triangle turn cos^2(arctan x) into 1/(1 + x^2), and what makes the square root in the arcsine derivative positive?

日本語版の動画は準備中です(英語版を表示しています)


読み込み中…

←前へ Inverse Functions and the Reflection Across y = x次へ The Derivative of aˣ and the Mystery Number M(a) →

まとめノート

    1. 1

      The derivative of tan⁡y\tan ytany and implicit differentiation

      Derive ddytan⁡y=1cos⁡2y=sec⁡2y\frac{d}{dy}\tan y = \frac{1}{\cos^2 y} = \sec^2 ydyd​tany=cos2y1​=sec2y with the quotient rule, then differentiate tan⁡y=x\tan y = xtany=x with respect to xxx and solve for y′y'y′.

    2. 2

      The right triangle that simplifies cos⁡2(arctan⁡x)\cos^2(\arctan x)cos2(arctanx)

      Draw the triangle with side xxx opposite yyy, adjacent side 111 and hypotenuse 1+x2\sqrt{1 + x^2}1+x2​, read off cos⁡y\cos ycosy, and finish with ddxarctan⁡x=11+x2\frac{d}{dx}\arctan x = \frac{1}{1 + x^2}dxd​arctanx=1+x21​.

    3. 3

      The derivative of arcsin⁡x\arcsin xarcsinx and its branch

      Differentiate sin⁡y=x\sin y = xsiny=x implicitly, rewrite cos⁡y\cos ycosy as 1−x2\sqrt{1 - x^2}1−x2​, state ddxarcsin⁡x=11−x2\frac{d}{dx}\arcsin x = \frac{1}{\sqrt{1 - x^2}}dxd​arcsinx=1−x2​1​, and record the branch choice behind the positive square root.

    2回中1回目