HP 39GS hp 39gs_user's guide_English_E_HDPMG39AE13.pdf - Page 158

n Takes the nth root of x. root NTHROOT value Example 3 NTHROOT 8 returns 2 Calculus functions The symbols for differentiation and integration are available directly form the keyboard- and S respectively-as well as from the MATH menu. ∂ Differentiates expression with respect to the variable of differentiation. From the command line, use a formal name (S1, etc.) for a non-numeric result. See "Finding derivatives" on page 13-21. ∂ variable(expression) Example ∂ s1(s12+3*s1) returns 2*s1+3 ∫ Integrates expression from lower to upper limits with respect to the variable of integration. To find the definite integral, both limits must have numeric values (that is, be numbers or real variables). To find the indefinite integral, one of the limits must be a formal variable (s1, etc). ∫ (lower, upper, expression, variable) See "Using formal variables" on page 13-20 for further details. Example ∫ (0,s1,2*X+3,X) finds the indefinite result 3*s1+2*(s1^2/2) See "To find the indefinite integral using formal variables" on page 13-23 for more information on finding indefinite integrals. 13-6 Using mathematical functions