Answer
$(x+(2+x^{2}))(x-(2+x^{2}))=-x^{4}-3x^{2}-4$
Work Step by Step
$(x+(2+x^{2}))(x-(2+x^{2}))$
Rewrite by removing the inner parentheses:
$(x+(2+x^{2}))(x-(2+x^{2}))=(x^{2}+x+2)(-x^{2}+x-2)=...$
Multiply each term of the first factor with every term of the second factor:
$...=-x^{4}+x^{3}-2x^{2}-x^{3}+x^{2}-2x-2x^{2}+2x-4=...$
Combine like terms and simplify:
$...=-x^{4}+(x^{3}-x^{3})+(-2x^{2}+x^{2}-2x^{2})+(-2x+2x)-4=$
$...=-x^{4}-3x^{2}-4$
