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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
01瞬間の変化率としての導関数 ― 平均の速さの二倍02時間のない変化率:気温の勾配と GPS の感度03代入で求まる極限、0/0、片側極限04連続性とは二つの数の比較:跳躍不連続点と除去可能な不連続点05無限大に発散する不連続点:1/x とその導関数06微分可能なら連続:一行で終わる証明と、0 でわらない理由問題セット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
01Average Rate Times Time: FTC Beats the Mean Value Theorem02Second Fundamental Theorem: Differentiate an Integral03Proving FTC1 and FTC2 with the Mean Value Theorem問題セット0/10問題セット20/10MIT 問題セット0/2
積分の応用
01The Natural Log Defined as an Area Under 1/t02Functions With No Formula: erf, Fresnel and Li(x)03Setting Up the Area Between Two Curves04Vertical vs Horizontal Slices: One Region, Two Integrals問題セット0/10問題セット20/10

このページは日本語版を準備中です

Functions With No Formula: erf, Fresnel and Li(x)

How do you sketch a function no formula can express, like the integral of e^(−t²), and why does it level off at √π/2?

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 The Natural Log Defined as an Area Under 1/t次へ Setting Up the Area Between Two Curves →

まとめノート

    1. 1

      Derivatives and shape of F(x)=∫0xe−t2 dtF(x) = \int_0^x e^{-t^2}\,dtF(x)=∫0x​e−t2dt

      Derive F′F'F′ and F′′F''F′′ from the Fundamental Theorem, record F(0)=0F(0) = 0F(0)=0 and F′(0)=1F'(0) = 1F′(0)=1, and state where FFF increases, its concavity on each side, and the inflection point.

    2. 2

      Odd symmetry F(−x)=−F(x)F(-x) = -F(x)F(−x)=−F(x)

      Reproduce the area argument on the bell curve e−t2e^{-t^2}e−t2, with area accumulated leftward from 000 counted negatively, and use it to reflect the right-hand branch of the sketch.

    3. 3

      Asymptotes ±π2\pm\frac{\sqrt{\pi}}{2}±2π​​ and the error function

      State the limits of FFF as x→±∞x \to \pm\inftyx→±∞ as half-bell areas, define erf⁡(x)=2π∫0xe−t2 dt\operatorname{erf}(x) = \frac{2}{\sqrt{\pi}}\int_0^x e^{-t^2}\,dterf(x)=π​2​∫0x​e−t2dt with its limit 111, and finish the sketch with both asymptotes.

    4. 4

      Fresnel integrals and the logarithmic integral

      Write the definitions of S(x)S(x)S(x), C(x)C(x)C(x) and Li⁡(x)\operatorname{Li}(x)Li(x), record the link between Li⁡(x)\operatorname{Li}(x)Li(x), counting primes and the Riemann hypothesis, and list the recipe: derivative, starting value, sketch.

    2回中1回目