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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

Net Change and Signed Area: Integrating Velocity

Why does integrating velocity give net change in position, and why does the area below the axis count as negative?

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…

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まとめノート

    1. 1

      Net change in position ∫abv(t) dt=x(b)−x(a)\int_a^b v(t)\,dt = x(b) - x(a)∫ab​v(t)dt=x(b)−x(a)

      Write the statement with v=x′v = x'v=x′, and record what each side means in driving terms: the odometer difference on the right, the accumulated speedometer readings on the left.

    2. 2

      The speedometer Riemann sum ∑v(ti) Δt\sum v(t_i)\,\Delta t∑v(ti​)Δt

      Set up the once-per-second thought experiment, write the distance covered in one interval and the sum over the trip, and state when it approximates the integral and that the integral is exact.

    3. 3

      Signed area: ∫02πsin⁡x dx=0\int_0^{2\pi} \sin x\,dx = 0∫02π​sinxdx=0

      Carry the sine computation through by the fundamental theorem to 000, then write the integral as area above the xxx-axis minus area below it, using the round trip as the motivating example.

    4. 4

      Net distance ∫abv dt\int_a^b v\,dt∫ab​vdt versus total distance ∫ab∣v∣ dt\int_a^b |v|\,dt∫ab​∣v∣dt

      Write both formulas side by side and record which one the plain definite integral gives and which one an odometer measures once the velocity changes sign.

    2回中1回目