Answer
$x^{2} -x^{4}$
Work Step by Step
$(x-x^{2})(x+x^{2})$
1. Square the first term. $(x)(x) = x^{2}$
2. Multiply the last terms inside each bracket together. $(-x^{2})(x^{2}) = -x^{4}$
3. Add your answers from steps 1-2 to get $x^{2} -x^{4}$.