# What can the comma symbol be used for on the CASIO fx-85ES PLUS scientific calculator?

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Scientific calculators have always have that comma or momayyez symbol. Mine, a CASIO fx-85ES PLUS, have it located at SHIFT + ). And everytime I think I'm using it correctly, it says syntax error, and the cursor jumps to whatever is before it.

My question is, how is that symbol used in some mathematical formula input in scientific calculators?

I think I need to add an " equals to something " before the symbol. But i cannot find any "equals to" sign ina ny calculators. Whoch led me to believe, it's there used as a multiple variable setter (like x = 1, -2).

• The decimal separator (usually dot or comma, depending on which country you are in) is definitely a mathematical symbol that you can use in mathematical formulas. But its implementation (mainly, whether it is dot or comma, and how it's interpreted) very much depends on the calculator ... – Matti P. Aug 15 '18 at 13:37
• Welcome to stackexchange. Your question is too general for us to help. We don't know what your calculator looks like, what you actually enter and what actually happens. Calculators in the English speaking world generally have a key with a dot on it to indicate that you have finished entering an integer and the decimal parts will follow. That dot is used to show results too. In other countries the dot is a comma. The calculator may or may not use that. – Ethan Bolker Aug 15 '18 at 13:37
• @apanpapan3: I hope you did not delete your answer because of my comment which was meant as a joke... – copper.hat Aug 15 '18 at 13:44
• I'm sorry for being too broad.. I'm using a "CASIO fx-85ES PLUS" scientific calculator.. And no it doesn't seem to be used simply as a decimal point.. I tried inputing "5*(1,2,3)" and it said syntax error. I also tried "100,500 * 3,00" and still returned syntax error – Andrew Angelo Barrientos Aug 15 '18 at 13:45
• I've voted to close because your real interest seems to lie in the syntax error returned by your calculator. Asking about whether a comma can be used in mathematics is pretty broad; commas might be used to separate items in a list or in a vector. But discussion of those uses will not clear up whatever you are trying to do with your calculator, and unless that can be tied to a mathematical task, questions about using the calculator are off-topic. – hardmath Aug 15 '18 at 14:02

1. To convert between rectangular and polar cooordinates. For example: $$\text{Pol}\left(\sqrt{2}\color{red},\sqrt{2}\right) \\ r=2,\theta=0.7853981 \\ \text{Rec}\left(\sqrt{2}\color{red},\pi\div4\right) \\ X=1,Y=1$$
2. To generate random integers, e.g. in the range $1$ to $6$: $$\text{RanInt#}(1\color{red},6)$$ Then keep pressing the '=' key.
3. To calculate logarithms to an arbitrary base, such as: $$\log(2\color{red},16) \\ 4$$