## Precalculus: Mathematics for Calculus, 7th Edition

$(x^{2}+4)(x^{4}-8x^{2}+16)$
Use the sum of cubes to solve. (1) $x^{6}+64$ (2) $(x^{2})^{3}+4^{3}$ (3) $(x^{2}+4)((x^{2})^{2}-2(x^{2})(4)+(4)^{2})$ (4) $(x^{2}+4)(x^{4}-8x^{2}+16)$