\(\Leftrightarrow\left(x+1\right)\left(x+2\right)-5\left(x-2\right)=10+x^2-4\)
\(\Leftrightarrow x^2+3x+2-5x+10-10-x^2+4=0\)
=>-2x+6=0
hay x=3(nhận)
đk : x khác 2 ; -2
<=> x^2 + 3x + 2 - 5x + 10 = 10 + x^2 - 4
<=> x^2 - 2x + 12 = x^2 + 6
<=> -2x + 6 =0 <=> x = 3 (tm)
⇔ \(\dfrac{\left(x+1\right)\left(x+2\right)-5\left(x-2\right)}{x^2-4}=\dfrac{10+x^2-4}{x^2-4}\) (đk: x≠ +-2)
⇔ \(\dfrac{x^2+2x+x+2-5x+10-x^2-6}{x^2-4}=0\)
⇒ \(-2x+6=0\)
⇒ \(x=3\left(tm\right)\)