Question
Simplify:
$\big(-3+\sqrt{5}\big)\big(-3-\sqrt{5}\big)$
$\big(-3+\sqrt{5}\big)\big(-3-\sqrt{5}\big)$
✓
Answer
$\big(-3+\sqrt{5}\big)\big(-3-\sqrt{5}\big)$
$=(-3)^2-\big(\sqrt{5}\big)^2$
$=9-5$
$=4$
$=(-3)^2-\big(\sqrt{5}\big)^2$
$=9-5$
$=4$
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