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How to convert any number (negative or positive) into a positive number.. For example, my input can be 4545 or -4545, I need the out come to be positive value 4545.

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2 Answers 2

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You just have to simply multiply by $-1$. For example if you have a number $-a$ then multiply by $-1$ to get $-a \times -1 =a$. If the number is positive then multiply by $1$.

Or if you are aware of the Absolute Value, then take the absolute value of the number.

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    This is the problem. I am getting the first value from an equation. I do not know it would be positive or negative. But I want it in positive. So I need to apply some equation on it if I am right.2011-05-28
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    cool. Absolute Value is working.2011-05-28
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With a calculator, you could make a number positive in one of two (simple) ways:

  • $\text{abs}(x)$
  • $\sqrt{(x^2)}$

The first one is recommended, but the second one will work as well as the square root function on most calculators returns the positive root. Squaring a real number always makes it positive, so taking the square root of a number squared returns the positive number.

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    Yes, by all means use $\operatorname{abs}(x)$! You don't want to waste time squaring and taking roots (you'll also have to cope with imprecisions)...2011-05-28
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    Precisely. The second option is a work-around only (like if your calculator doesn't have an absolute-value function).2011-05-28
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    In textbooks, the first one is often written $\lvert x\rvert$.2011-05-28
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    no, square root give two results: +/-2018-05-30
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    @Sergei: to be pedantic, the square root symbol always means the principal square root, which is positive.2018-05-30
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    Thanks @El'endiaStarman for clarification. You helped me to see the difference between the symbol and ^(1/2)2018-07-11