HP 48gII hp 48gII_user's manual_English_E_HDPMSG48E67_V2.pdf - Page 449

Anti-derivatives and integrals An anti-derivative of a function f(x) is a function F(x) such that f(x) = dF/dx. For example, since d(x3) /dx = 3x2, an anti-derivative of f(x) = 3x2 is F(x) = x3 + C, where C is a constant. One way to represent an anti-derivative is as a ∫ indefinite integral, i.e., f (x)dx = F (x) + C , if and only if, f(x) = dF/dx, and C = constant. Functions INT, INTVX, RISCH, SIGMA and SIGMAVX The calculator provides functions INT, INTVX, RISCH, SIGMA and SIGMAVX to calculate anti-derivatives of functions. Functions INT, RISCH, and SIGMA work with functions of any variable, while functions INTVX, and SIGMAVX utilize functions of the CAS variable VX (typically, 'x'). Functions INT and RISCH require, therefore, not only the expression for the function being integrated, but also the independent variable name. Function INT, requires also a value of x where the anti-derivative will be evaluated. Functions INTVX and SIGMAVX require only the expression of the function to integrate in terms of VX. Some examples are shown next in ALG mode: Page 13-14