Question

please solve : [7+3√5\3+√5]-[7-3√5\3-√5]

Answer 1

Mark as brainelist dont forget that
$( \frac{7 + 3 \sqrt{5} }{3 + \sqrt{5} } ) - ( \frac{7 - 3 \sqrt{5} }{3 - \sqrt{5} } ) \\ = \frac{(7 + 3 \sqrt{5})(3 - \sqrt{5}) - (7 - 3 \sqrt{5} )(3 + \sqrt{5} ) }{ {3}^{2} - {( \sqrt{5}) }^{2} } \\ = \frac{21 - 7 \sqrt{5} + 9 \sqrt{5} - 15 - 21 - 7 \sqrt{5} + 9 \sqrt{5} + 15 }{4} \\ = \frac{4 \sqrt{5} }{4} \\ = \sqrt{5}$