`x^2+2x-5`
`=(x^2+2x+1)-6`
`=(x+1)^2-\sqrt6^2`
`=(x+1+\sqrt6)(x+1-\sqrt6)`
\(x^2+2x-5\)
\(= x^2+2x+1-6\)
\(= (x+1)^2-6\)
\(= (x+1)^2-\left(\sqrt{6}\right)^2\)
\(= \left(x+1-\sqrt{6}\right)\left(x+1+\sqrt{6}\right)\)
\(x^2+2x-5\)
\(=x^2+2x+1-6\)
\(=\left(x+1\right)^2-6\)
\(=\left(x+1-\sqrt{6}\right)\left(x+1+\sqrt{6}\right)\)