Question

factorise p^4-81 help me....

Answer 1

p⁴-81
=(p²)²-(9)²
=(p²-9)(p²+9)

Answer 2

hey

${p {}^{2 {}^{2} } } - {3 {}^{2} }^{2}$
as we know
${a}^{2} - {b}^{2} \\ = (a + b)(a - b)$
Therefore
$( {p}^{2} + {3}^{2} )( {p}^{2} - {3}^{2} ) \\ ( {p}^{2} + {3}^{2} )(p + 3)(p - 3)$
Hope it helps to you.