I want to downlaod fx115es calculator to used to solve

Press SHIFT SETUP 1

The calculator does not have a TVM function/feature.

Press [SHIFT][MODE] to enter (SetUp). Select [2:LineIO] and you will be rid of the MATH Input/Output. You will lose some nifty features, like the stacked fractions, the radicals, but that is your choice.

Cheers.

The inverse sine is defined only for numbers in the range [-1, +1].
The sine of a number is at most 1.0. There is no number whose sine is 1.5, which is what you're asking for.
The same applies to the cosine and inverse cosine.

Not all calculators have that. The Fx115ES and the FX991 ES have a lot more options thatn the FX300Es and FX350ES. I believe you only have COMP (general computational mode), Table and STAT.
Why? It was not designed that way.

support.casio.com/pdf/004/fx-115ES_991ES_Eng.pdf -
It is all explained in the above manual.

To clear the display, press the AC button. To enter powers press the power key, labeled x with a raised small solid square. To use it enter the number: if the screen displays x with a dark square enter the exponent in the raised square. If the display shows a ^, enter exponent after the caret ^. Close any parentheses by entering the matching right parenthesis.

Press SHIFT MATH 2 to switch to the LineIO mode. You won't see fractions then. However, if magnitude of the number is too large or too small, the calculator will switch to scientific notation in order to fit into the display.

Hello,

Use your internet seach engine or go to the casio worldwide web site. A google search returned this link to the New-Zealand site.

http://casionz.co.nz/Site/Pronto/Files/user_manuals/FX-115ES%20991ES.PDF

Hope it helps

According to the manual for the Casio FX115ES, the largest matrix it solves is a 3x3.