# first vs second fundamental theorem of calculus

The Second Part of the Fundamental Theorem of Calculus. The Two Fundamental Theorems of Calculus The Fundamental Theorem of Calculus really consists of two closely related theorems, usually called nowadays (not very imaginatively) the First and Second Fundamental Theo-rems. This lesson contains the following Essential Knowledge (EK) concepts for the *AP Calculus course.Click here for an overview of all the EK's in this course. The first part of the theorem says that if we first integrate $$f$$ and then differentiate the result, we get back to the original function $$f.$$ Part $$2$$ (FTC2) The second part of the fundamental theorem tells us how we can calculate a definite integral. Note that the ball has traveled much farther. In this article, let us discuss the first, and the second fundamental theorem of calculus, and evaluating the definite integral using the theorems in detail. Of the two, it is the First Fundamental Theorem that is the familiar one used all the time. The second fundamental theorem of calculus holds for f a continuous function on an open interval I and a any point in I, and states that if F is defined by the integral (antiderivative) F(x)=int_a^xf(t)dt, then F^'(x)=f(x) at each point in I, where F^'(x) is the derivative of F(x). The first full proof of the fundamental theorem of calculus was given by Isaac Barrow. Area Function - The integral has a variable as an upper limit rather than a constant. A few observations. FT. SECOND FUNDAMENTAL THEOREM 1. James Gregory, influenced by Fermat's contributions both to tangency and to quadrature, was then able to prove a restricted version of the second fundamental theorem of calculus in the mid-17th century. The first theorem is instead referred to as the "Differentiation Theorem" or something similar. Introduction. Thus if a ball is thrown straight up into the air with velocity the height of the ball, second later, will be feet above the initial height. As we learned in indefinite integrals, a primitive of a a function f(x) is another function whose derivative is f(x). It has gone up to its peak and is falling down, but the difference between its height at and is ft. EK 3.3A1 EK 3.3A2 EK 3.3B1 EK 3.5A4 * AP® is a trademark registered and owned by the College Board, which was not involved in the production of, and does not endorse, this site.® is a trademark The Second Fundamental Theorem of Calculus establishes a relationship between a function and its anti-derivative. Specifically, for a function f that is continuous over an interval I containing the x-value a, the theorem allows us to create a new function, F(x), by integrating f from a to x. There are several key things to notice in this integral. You already know from the fundamental theorem that (and the same for B f (x) and C f (x)). When you see the phrase "Fundamental Theorem of Calculus" without reference to a number, they always mean the second one. Finally, you saw in the first figure that C f (x) is 30 less than A f (x). The first part of the theorem says that: The second figure shows that in a different way: at any x-value, the C f line is 30 units below the A f line. The first part of the fundamental theorem stets that when solving indefinite integrals between two points a and b, just subtract the value of the integral at a from the value of the integral at b. The fundamental theorem of calculus justifies the procedure by computing the difference between the antiderivative at the upper and lower limits of the integration process. - The variable is an upper limit (not a lower limit) and the lower limit is still a constant. First fundamental theorem of calculus: $\displaystyle\int_a^bf(x)\,\mathrm{d}x=F(b)-F(a)$ This is extremely useful for calculating definite integrals, as it removes the need for an infinite Riemann sum. The Second Fundamental Theorem of Calculus shows that integration can be reversed by differentiation. 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