Question
State whether the following number is rational or irrational:$(2+\sqrt{2})(2-\sqrt{2})$
✓
Answer
$(2+\sqrt{2})(2-\sqrt{2}) $
$=(2)^2-(\sqrt{2})^2 $
$=4-2$
$ =$2 which is rational.
$=(2)^2-(\sqrt{2})^2 $
$=4-2$
$ =$2 which is rational.
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