Question

factorise using identity

Answer 1

hello.......... ^_^

here is your answer....

factorise
${a}^{4} - {b}^{4}$
solution
${a}^{4} - {b}^{4} \\ = {( {a}^{2} )}^{2} - {( {b}^{2}) }^{2} \\ = ({a}^{2} + {b}^{2} )( {a}^{2} - {b}^{2} ) \\ = ({a}^{2} + {b}^{2} )( \: \: \: {(a})^{2} - { \: (b)}^{2} \: \: ) \\ = ( {a}^{2} + {b}^{2} ) \: (a + b)(a - b) \\ = {(a + b)}^{2} (a + b)(a - b) \\ = (a + b)(a + b)(a + b)(a - b)$


hope this helps..... ^_^