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Comment by graycat

Part I

(1) Calculus

Generally should have college freshman and sophomore calculus.

(1.1) Functions

So, there can understand better what a function is. E.g., function

     f(x) = 3x^2 + 1.
(1.2) Derivatives

Then will learn how to find the slope of the graph of a function. That is the derivative of the function. E.g., for function f with f(x) = 3x + 2, as in high school algebra, the slope is 3. Then for each x, the derivative of f at x is just 3.

The derivative of function f is denoted by either of

     f'(x) = d/dx f(x)
E.g., for function f(x) = 3x^2 + 1 it turns out that

     f'(x) = 6x.
(1.3) Integration

For function

     g(x) = 6 x
maybe we want to know what function f(x) will give us

     f'(x) = g(x)
Finding such a function f is anti-differentiation, that is, undoes differentiation. So, sure,

     f(x) = 3x^2 + C
for any constant C.

Such anti-differentiation is also the way to find the area under a curve. So, can use that to find the area of a circle, volume of a cylinder, etc. Doing that the anti-differentiation is integration.

The fundamental theorem of calculus shows how differentiation and integration are related.

(1.4) Analytic Geometry

Commonly taught at the beginning of a calculus course is analytic geometry.

So, take a cone an cut it. Then the cut surfaces will be one of a circle, an ellipse, a parabola, a hyperbola, or just two crossed straight lines. So, those curves are from a cone and are the conic sections.

There is some simple associated algebra.

Conic sections are important off and on; e.g., applied math is awash in circles; the planets move in ellipses; a baseball moves in a parabola or nearly so; an electron moving toward a negative charge will turn away from that charge in a hyperbola.

It turns out that in linear algebra (below) circles and ellipses are important.

(1.5) Role of Calculus

Calculus was invented by Newton as part of working with force and acceleration for understanding the motion of the planets.

E.g., if at time t function d(t) gives distance traveled, then function v(t) = d'(t) is the velocity at time t and function a(t) = v'(t) is the acceleration at time t.

Then Newton's second law is

     F(t) = m a(t)
where F(t) is the force at time t applied to mass m.

Calculus is the first approach to the analysis of continuous change and is a pillar of civilization.

Knowledge of calculus will commonly be assumed in work in ML/AL, data science, statistics, optimization, applied math, engineering, etc.

E.g., a lot in ML, AI, and data science is getting best fits to data; best fitting is to minimize errors in the fit; such minimization is mostly a calculus problem; one of the main steps in ML is steepest descent, and that is from a derivative.

Probability theory (e.g., evaluating coin tossing, poker hands, accuracy in ML) will be important in ML/AI, etc.; two of the basic notions in probability are cumulative distributions and density distributions; the cumulative is from an integration, and the density is from a differentiation.

parent graycat 9 years ago

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