Question

if a=1+square root 7 find the value of -6/a​

Answer 1

ANSWER

Given:

$a = 1 + \sqrt{7}$

To find:

$\frac{ - 6}{a}$

Solution:

$\frac{ - 6}{a} = \frac{ - 6}{1 + \sqrt{7} }$

$= > \frac{ - 6(1 - \sqrt{7)} }{1 + \sqrt{7}(1 - \sqrt{7}) }$

$= > \frac{ - 6 + 6 \sqrt{7} }{ {1}^{2} - { \sqrt{7} }^{2} }$

$= > \frac{6 \sqrt{7 } - 6}{1 - 7}$

$= > \frac{6 \sqrt{7} - 6}{ - 6}$

$= > \frac{6 - 6 \sqrt{7} }{6}$