\[\boxed{\text{954.}\text{\ }еуроки - ответы\ на\ пятёрку}\]
\[\textbf{а)}\ p^{4} - 16 = \left( p^{2} - 4 \right)\left( p^{2} + 4 \right) =\]
\[= (p - 2)(p + 2)(p^{2} + 4)\]
\[\textbf{б)}\ x^{4} - 81 =\]
\[= \left( x^{2} - 9 \right)\left( x^{2} + 9 \right) =\]
\[= (x - 3)(x + 3)(x^{2} + 9)\]
\[\textbf{в)}\ y^{8} - 1 = \left( y^{4} - 1 \right)\left( y^{4} + 1 \right) =\]
\[= \left( y^{2} - 1 \right)\left( y^{2} + 1 \right)\left( y^{4} + 1 \right) =\]
\[= (y - 1)(y + 1)\]
\[(y^{2} + 1)(y^{4} + 1)\]
\[\textbf{г)}\ a^{4} - b^{8} =\]
\[= \left( a^{2} - b^{4} \right)\left( a^{2} + b^{4} \right) =\]
\[= (a - b^{2})(a + b^{2})(a^{2} + b^{4})\ \]