Question

State, whether the following numbers are rational or irrational.​
$(2+\sqrt{2})(2-\sqrt{2}$)

Answer 1

Step: Check whether the expression is rational or irrational.​
$(2+\sqrt{2})(2-\sqrt{2})$
$=2^2-(\sqrt{2}{)}^2$
$=4-2$
$=2$
Which is a rational number
Therefore $(2+\sqrt{2})(2-\sqrt{2}$) is a rational number