Question

rationalise the denominator of each of the following 4/√11-√7​

Answer 1

Step-by-step explanation:

$\frac{4}{ \sqrt{11} - \sqrt{7} } \\ by \: rationalising \: \\ = \frac{4}{ \sqrt{11} - \sqrt{7} } \times \frac{ \sqrt{11} + \sqrt{7} }{ \sqrt{11} + \sqrt{7} } \\ = \frac{4( \sqrt{11} + \sqrt{7} ) }{ \sqrt{11 ^{2} } - \sqrt{7 ^{2} } } \\ = \frac{4( \sqrt{11} + \sqrt{7}) }{4}$