Question

Solve the following equation for the variable:
\[x^2=4\]

Answer 1

\[x=\pm 2\] ?

Answer 2

@ash2326 @amistre64

Answer 3

yes.

Answer 4

what if : \(x=\sqrt{4}\)

Answer 5

\[x ^{2}=+4\]

Answer 6

I wonder that there is something I am forgetting..

@ash2326 can u remind me?

Answer 7

x = sqrt4
and
x^2 = 4

Answer 8

isn't something like this? that has two diff. soln ?

Answer 9

if we have
\[x=\sqrt 4\]
then x=2
if
\[x^2=4\]
\[x^2-4=0\]
\[(x+4)(x-4)\]

\[x=\pm 2\]

Answer 10

oops (x+2)(x-2)

Answer 11

Exactly but why is it so that x = \sqrt{4} then we have x = 2 ? and not x = -2..

Answer 12

square root is defined like this. Its range is positive real no.s only

Answer 13

any example?

Answer 14

\(x^2 = 4\)
=>
\(x = \pm\sqrt{4}\)

Answer 15

your question is an example of this
\[y=\sqrt {x}\]
domain = \(x\ge 0\)
range=\(y \ge=0\)

Answer 16

Oh gotcha...

Thanks @ash2326 and @ganeshie8 (:))

Answer 17

welcome @mathslover :)

Answer 18

it's like this\[x^2=4\] then take mode of both sides \[|x^2|=4\]--->\[|x|^2=4\]---->\[|x|=2\]----->\[x=+2,-2\]