[HP 35s] Finding the minimum of a FCN

[Dieter]

(07-03-2015 11:15 PM)Marcio Wrote:  Basically, what I am trying to do is to find a local minimum by solving f'(x)=0, which in this case is 5/2.

You might be interested in another method of finding local extrema with a completely different approach. Take a look at this thread in the old forum, especially message #12.

In your function be sure to replace x² with x*x since on the 35s the x² function does not work in the complex domain. Or use Horner's method:

Code:

LBL Y
RCL X
5
-
RCLx X
6
+
RTN

Set a suitable h:
1 E-6 [STO] H

Find the minimum between x=1 and 5:

1 [ENTER] 5 XEQ E [ENTER]
SOLVING
E= 2,5000

BTW, the program will also find the two roots on both sides of the minimum:

0 [ENTER] 2,5 XEQ Z [ENTER]
SOLVING
Z= 2,0000

2,5 [ENTER] 5 XEQ Z [ENTER]
SOLVING
Z= 3,0000

Dieter