Multiply: (x2+1)(x2−3)(x^2 + 1)(x^2 - 3)(x2+1)(x2−3).
x4−2x2−3x^4 - 2x^2 - 3x4−2x2−3
x4−3x^4 - 3x4−3
x4+2x2−3x^4 + 2x^2 - 3x4+2x2−3
x4−2x2+3x^4 - 2x^2 + 3x4−2x2+3