# How do you use the binomial formula to find expand (x^2y - 1)^5?

（x^2y-1)^5
$= 5 c 5 {\left({x}^{2} y\right)}^{5} + 5 c 4 {\left({x}^{2} y\right)}^{4} \left(- 1\right) + 5 c 3 {\left({x}^{2} y\right)}^{3} {\left(- 1\right)}^{2} + 5 c 2 {\left({x}^{2} y\right)}^{2} {\left(- 1\right)}^{3} + 5 c 1 \left({x}^{2} y\right) {\left(- 1\right)}^{4} + 5 c 0 {\left({x}^{2} y\right)}^{0} {\left(- 1\right)}^{5}$