I have a question here...
Usually, for
$x^2 = 4$
$x=\sqrt{4}$
$x=±2$
But if the question is like this :
$y^2 = (x+2)(x+2)$
$y^2 = (x+2)^2$
If I want to find $y$ in term of $x$,I will put square root on both sides.
y = ±(x+2)
So I'm wondering about whether I should put the sign ± in front of $(x+2)$.This because I think the answer should be $(x+2)$ only because the $(x+2)^2$ is the product of $(x+2)(x+2)$ as shown in the equation and not $(-（x+2)) (-(x+2))$. Anyone can tell me ? Thank you :D
Actually, the solution is $\pm (x+2)$ (as MrYouMath pointed out in the comments). This is because if you multiply $-(x+2)$ by itself, you get $(-(x+2))(-(x+2))$, which is equivalent to $(-1)(-1)(x+2)(x+2)$ by the commutative laws of multiplication. Finally, the first product is $-1 \times -1=1$, so indeed you would get $(-(x+2))^2=(x+2)^2=y^2$, meaning both are a solution to your equation.