Hello! I would like help in troubleshooting with programming on my fx-7400GIII. I'm in uni and we are currently working on numerical integration. For our class our professor had us program 4 different methods for this:

The rectangle method, the trapezoid method, the bisection method and Newton- Rhapson's method.

I've gotten everything to work except for Newton- Rhapson. Our teacher is a Texas guy and he couldn't solve how to get the script for this method to work on my calculator so that it actually functions. I have an exam in 2 days and would love if somebody could help me out a little. The issue seems to be with the nDeriv (dy/dx on casio?) function. When i try to run the script i just get an error, and the only difference between this script and the 3 others that i got working no problem is that this one has a derivative function in it. This is the script I'm trying to run:

ClrText

"LOSER Y1=0."

"GISSNING: "?→X

"ITERATIONER: "?→N

For 1→I To N

X-Y1(X)/nDeriv(Y1,X,X)→X

Next

"LOSNING: "

X

I've traded the "nDeriv" which doesn't seem to exist on Casio for "dy/dx" but something still isn't working. My professor thought it might have something to do with the format of (Y1,X,X) within the parenthesis, but I don't know.

Any solution to this problem would be extremely appreciated! Exam is in 2 days... And I can't figure it out!!