Quick Tips for the Casio fx-115ES Plus and fx-991EX Classwiz
This applies to other similar and earlier Casio calculators. Please consult your manual if you have a different model. This refers to Casio models that have textbook entry and output, such as the fx-115ES (Plus), fx-991ES (Plus), fx-991EX Classwiz, and fx-570EX Classwiz.
Always Get an Approximate Answer
In the Math input mode, the Casio attempts to return an exact answer (fractions, terms of π, terms of square roots). If you want to get an approximate answer from the get go, all that is needed is to press [SHIFT], [ = ] (≈).
Using a Formula
Steps:
1. Enter your formula.
2. Press [CALC].
3. Enter a value for each variable prompted, then press [ = ].
4. For the Classwiz models: You can scroll up and down between variables.
Example:
(A^2 + B^2)^(1/3)
A = 3, B = 4, result 2.924017738
A = 5, B = 10, result 5
Solve f(X) = 0
Steps:
1.
Enter f(X). On the Classwiz
series, you can use the [ x ] button.
There is no need to enter the “=0”.
2.
Press [SHIFT], [ CALC ] (SOLVE)
3.
Enter a guess and press [ = ].
Example:
(Radians Mode)
X sin(X) – 1 with guess X = π, result: X = 2.772604708
Tip:
I prefer to use X, but you should be able to use any of the other
variables available (A, B, C, D, E*, F*, Y, M).
*E and F are available on later models.
Solve f(X) = g(X)
Steps:
1.
Enter f(X). On the Classwiz
series, you can use the [ x ] button.
2.
Press [ALPHA], [CALC] ( = ) for the equals symbol. This is very important. Then enter g(X).
3.
Press [SHIFT], [ CALC ] (SOLVE)
4.
Enter a guess and press [ = ] (the equals key).
Example:
ln(X) = X^2 – 2 with guess X = 1,
result X = 1.564462259
Unit Conversion
1.
Enter a number that is needed to be converted.
2.
Depending on what version for Casio you have:
For the fx-991EX Classwiz (I think
this applies to the fx-570EX Classwiz as well):
Press [SHIFT] [ 8 ] (CONV). Select
a category and select a conversion.
For the fx-115ES PLUS and earlier
models (non-Classwiz models): Press
[SHIFT] [ 8 ] (CONV) and enter a code.
For the fx-115ES PLUS, the conversions are listed both in the manual and
the hard slide on case.
Here is a sample of the conversions
offered on the fx-115ES PLUS:
01
|
in → cm
|
19
|
km/h → m/s
|
35
|
lbf/in^2 → kPa
|
02
|
cm → in
|
20
|
m/s → km/h
|
36
|
kPa → lb/in^2
|
07
|
mi → km
|
21
|
oz → g
|
37
|
°F → °C
|
08
|
km → mi
|
22
|
g → oz
|
38
|
°C → °F
|
23
|
lb → kg
|
24
|
kg → lb
|
3.
Press [ = ].
Please be aware the older models may
not have the conversion function.
Factoring an Integer
‘1.
Enter an integer then press [ = ].
‘2.
Press [SHIFT], [ ° ‘ ‘’ ] (FACT)
Examples:
188 = 2^2 * 47
2506 = 2 * 7 * 179
Please be aware the older models may
not have the factoring function.
Calculus
Remember for derivative (d/dx),
integral ( ∫ ), sum ( Σ ), and product ( Π )*, the variable used is X. *Product may not be available on all
models.
Inverse and Determinant of a Matrix
For these calculators, matrices are a
separate mode. I assume that you know
how to edit and define matrices.
Casio fx-115 ES Plus and Non-Classwiz Modes that have a Matrix
mode:
Matrices are mode 6 (at least for the
fx-115EX Plus.)
Inverse:
[SHIFT] [ 4 ] (MATRIX), choose 3, 4,
or 5 for Matrix A, B, or C respectively, [ x^-1 ], [ = ].
Determinant:
[SHIFT] [ 4 ] (MATRIX), 7 for det,
[SHIFT] [ 4 ] (MATRIX), choose 3, 4, or 5 for Matrix A, B, or C respectively, [
= ].
Casio fx-991EX Classwiz and other Classwiz models:
Matrices are mode 4 (matrix icon).
Inverse:
[OPTN], choose 3, 4, 5, or 6 for
Matrix A, B, C, or D respectively, [ x^-1 ], [ = ]
Determinant:
[OPTN], [ down ], 2 for det, [OPTN],
choose 3, 4, 5, or 6 for Matrix A, B, C, or D respectively, [ = ].
Hope you find these tips helpful. Have a great day!
Eddie
This blog is property of Edward
Shore. 2015.