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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 set0/3
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 ContinuousProblem set0/10Problem set 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 RulesProblem set0/10Problem set 20/10MIT problem set0/1
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 InductionProblem set0/10Problem set 20/10MIT problem set0/2
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 ArcsineProblem set0/10Problem set 20/10MIT problem set0/1
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 eProblem set0/10Problem set 20/10MIT problem set0/1
Applications of Differentiation
01Linear Approximation: A Curve Is Its Tangent Line02Five Linear Approximations at Zero03Combining Approximations, from Algebra to GPS Clocks04Quadratic Approximation: The Best-Fit ParabolaProblem set0/10Problem set 20/10MIT problem set0/1
01Linear Approximation as a Proportionality Rule02Quadratic Approximation: Why the ½, and Products03Curve Sketching: The Sign of f′ and Critical Points04Curve Sketching: Ends, Concavity and InflectionProblem set0/10Problem set 20/10MIT problem set0/1
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 OccurProblem set0/10Problem set 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 TankProblem set0/10Problem set 20/10MIT problem set0/4
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 + xProblem set0/10Problem set 20/10MIT problem set0/2
Integration
01Differentials: dy = f′(x) dx and the Cube Root of 64.102Antiderivatives Differ Only by a Constant03Integration by Substitution and Advanced GuessingProblem set0/10Problem set 20/10MIT problem set0/1
01Separation of Variables: dy/dx = −xy and the Bell Curve02General Solutions: Signs, Constants and Initial Conditions03Orthogonal Trajectories: Parabolas and Crossing EllipsesProblem set0/10Problem set 20/10MIT problem set0/1
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 LoansProblem set0/10Problem set 20/10MIT problem set0/1
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 LimitsProblem set0/10Problem set 20/10MIT problem set0/1
01Average Rate Times Time: FTC Beats the Mean Value Theorem02Second Fundamental Theorem: Differentiate an Integral03Proving FTC1 and FTC2 with the Mean Value TheoremProblem set0/10Problem set 20/10MIT problem set0/2
Applications of Integration
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 IntegralsProblem set0/10Problem set 20/10
01The Disk Method: Volume of a Ball and a Spherical Cap02The Shell Method: Volume of a Parabolic Cauldron03Units Matter: Why y = x² Is Not Scale-InvariantProblem set0/10Problem set 20/10MIT problem set0/1

Units Matter: Why y = x² Is Not Scale-Invariant

How can one cauldron formula give 16 liters in centimeters and 1600 liters in meters, and both be right?


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    1. 1

      The paradox: a=100a = 100a=100 cm against a=1a = 1a=1 m

      Compute π2a2\frac{\pi}{2}a^22π​a2 both ways with the conversions written out, 1000 cm3=11000\ \text{cm}^3 = 11000 cm3=1 liter and 1 m3=106 cm31\ \text{m}^3 = 10^6\ \text{cm}^31 m3=106 cm3, reaching about 16 liters and about 1600 liters.

    2. 2

      Two cauldrons from one equation

      Find the rim radius in each reading of y=x2y = x^2y=x2, sketch the 20 cm wide vessel and the 2 m wide vat to one scale, and record which holds which volume.

    3. 3

      Why y=x2y = x^2y=x2 is not scale-invariant

      Write that yyy is a length while x2x^2x2 is a length squared, and state the rule: compute with unit-less numbers and attach the units to the answer at the end.

    4. 4

      Setup of the boiling cauldron

      Record the temperature T=100−30yT = 100 - 30yT=100−30y and that the cauldron will be sliced horizontally into disks of volume πx2 dy\pi x^2\,dyπx2dy, leaving the heat integral itself for later.

    Attempt 1 of 2