Question

$(7 + \sqrt{11})(7 - \sqrt{11}) =$
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Answer 1

Answer:

$\red{38}$

Step-by-step explanation:

$(7 + \sqrt{11} )(7 - \sqrt{11} ) \\ \\ = {7}^{2} - {( \sqrt{11}) }^{2} \\ \\ = 49 - 11 \\ \\ = 38$

$\huge \green\dag \: \: \rm{ \gray{CONCEPT \: \: USED}} \\ \\ (a + b)(a - b) = {a}^{2} - {b}^{2}$

HOPE IT HELPS YOU !

THANKS !

Answer 2

Question -

$Find \: the \: value \: of \: (7 + \sqrt{11})(7 - \sqrt{11} )$

Solution -

$= (7 + \sqrt{11} )(7 - \sqrt{11} )$

$= {(7)}^{2} - {( \sqrt{11} })^{2}$

$= 49 - 11$

$= 38$

Formula used here -

$(a + b)(a - b) = {a}^{2} - {b}^{2}$