Question

Solve the following equation:
$(x^2-4)\sqrt{x+1}=0$

Answer 1

$(x^2-4)\sqrt{x+1}=0$

$\Rightarrow x^2-4=0$ or/and, $\sqrt{x+1}=0$

$\Rightarrow (x-2)(x+2)=0,\sqrt{x+1}=0$

$\Rightarrow x=2,-2$ or $(x+1)=0\Rightarrow x=-1$

So, $x$ can be either $-1,-2or2$