Question

If
$a = \frac{2 - \sqrt{5} }{2 + \sqrt{5} } \: \: and \: \: b = \frac{2 + \sqrt{5} }{2 - \sqrt{5} }$
find
${a}^{2} - {b}^{2}$
​

Answer 1

ANSWER IS IN THE PHOTO CHECK!!!!!