Question
find the value of $: \operatorname{cosec}^2 60^\circ- \tan^2 30^\circ$
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Answer
$\operatorname{cosec}^2 60^\circ – \tan^2 30^\circ =$
$\left(\frac{2}{\sqrt{3}}\right)^2-\left(\frac{1}{\sqrt{3}}\right)^2$
$=\frac{4}{3}-\frac{1}{3}$
$=1$
$\left(\frac{2}{\sqrt{3}}\right)^2-\left(\frac{1}{\sqrt{3}}\right)^2$
$=\frac{4}{3}-\frac{1}{3}$
$=1$
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