In the second part of the Fundamental Theorem of Calculus, we learn how to evaluate definite integrals. A definite integral represents the area under a curve between two specified points.

To evaluate a definite integral using the Fundamental Theorem of Calculus, we first find the antiderivative of the integrand. Then, we subtract the value of the antiderivative at the lower bound from the value at the upper bound.

For example, let's say we want to find the area under the curve of the function f(x) = 2x between x = 1 and x = 3. First, we find the antiderivative of the function, which is F(x) = x^2. Next, we substitute the upper and lower bounds into F(x) and subtract the results: F(3) - F(1) = 9 - 1 = 8. Therefore, the area under the curve is 8 square units.

By following this process, we can evaluate definite integrals and determine the area between any two points on a curve.