`(x^2 -8)^2 -36`
`=(x^2 -8 -6)(x^2 -8 +6)`
`=(x^2 -14)(x^2 -2)`
`(x^2 - 8)^2 - 36`
`= (x^2 - 8)^2 - 6^2`
`= (x^2 - 8 + 6) (x^2 - 8 - 6)`
`= (x^2 - 2) (x^2 - 14)`
\(\left(x^2-8\right)^2-36\)
\(=\left(x^2-8-6\right)\left(x^2-8+6\right)\)
\(=\left(x^2-14\right)\left(x^2-2\right)\)