[Math] How to take integral of absolute value(x) on a Casio fx-991ms

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I don't know if this is the correct place for this question, if there is a more appropriate forum please let me know.

Trying to solve the probability density function which has an absolute value in it, how can I integrate an absolute value on a Casio fx-991ms calculator? In order to enter absolute value (x) I need to switch to Mode 2, but once I do that everything I entered for the integral disappears. If I try to do this in Mode 2 to begin with than the integral symbol simply does not work in Mode 2.

Best Answer

You could try taking the (non-negative) square-root of the square, since $$|x|=\sqrt{x^2}$$ for all real numbers

Related Solutions

[Math] How to solve equations with Casio FX-85WA calculator

Going swiftly through the calculators's Manual I found this section which explains the only use of the $X\ \& \ Y$ buttons:

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Hence the confirmation of what you suspected: this calculator does not solve any equations

[Math] Why doesn’t the TI-84 give me an exact value when calculating scientific notations

The calculator automatically uses scientific notation for numbers smaller than $0.001$ in absolute value, no matter what your mode settings are; this cannot be overridden.

The most straightforward way to get the calculator to immediately tell you how many zeroes there are after the decimal, in such a case, is to add $1$:

0.17^4
       8.3521e-4
Ans+1
      1.00083521

Just ignore the $1$ in front of the decimal point and you have the answer you want.

Note that in general, this will lose you precision:

0.17^8
  6.975757441e-7
Ans+1
     1.000000698

In this case, it's not too bad: we can use the second output to count zeroes and the first for more digits. Sometimes, it will lose you all of the precision:

0.17^16
  4.86611919e-13
Ans+1
               1

But in this last example, maybe you don't want the number as a decimal after all.

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Related Solutions

[Math] How to solve equations with Casio FX-85WA calculator

[Math] Why doesn’t the TI-84 give me an exact value when calculating scientific notations

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