How to find two square roots of a number?

Question

How to find two square roots of a number?

1 Answer

Impact of this question

5999 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-05-31T22:33:48

I will assume that behind this question is a myth that there is such a thing as, for example, "The square root of 2".

In fact for any number $a$ (in $RR$ or $CC$ ), if $r$ is a square root of $a$ then $-r$ is also a square root of $a$ .

If $a in RR$ and $a > 0$ then $a$ has two real square roots - the positive square root that we represent by the symbols $sqrt(a)$ and the negative square root, which is $-sqrt(a)$ .

If $a in RR$ and $a = 0$ then $a$ has one (repeated) square root, viz $0$ .

If $a in RR$ and $a < 0$ then $a$ has two pure imaginary square roots, $sqrt(-a)*i$ and $-sqrt(-a)*i$

Science

Math

Humanities

... and beyond

How to find two square roots of a number?

1 Answer

Related questions

Impact of this question