HP 15c Scientific 000–, 002–, 003–, 004–, |¥ 000–, 001–42,21,0

Section 14: Numerical Integration 195

In Run mode:

2.Key the lower limit of integration (a) into the X-register, then press vto lift it into the Y-register.

3.Key the upper limit of integration (b) in to the X-register.

4.Press ´ffollowed by the label of your subroutine.

Example: Certain problems in physics and engineering require calculating Bessel functions. The Bessel function of the first kind of order 0 can be expressed as

		1		π
J0	(x) =			cos (x sinθ) dθ .
		π ∫0
Find
				π
			π ∫0
J	0 (1) =		1	cos (sinθ) dθ .

In Program mode, key in the following subroutine to evaluate the function f(θ) = cos (sin θ).

KeystrokesDisplay

¥ 000–

´CLEAR M 000–

´b0	001–42,21, 0
[	002–	23
\	003–	24
n	004–	43 32

Program mode.

Clear program memory. Begin subroutine with a

binstruction. Subroutine assumes a value of θ is in X-register. Calculate sin θ.

Calculate cos (sin θ).

Now, in Run mode key the lower limit of integration into the Y-register and the upper limit into the X-register. For this particular problem, you also need to specify Radians mode for the trigonometric functions.