Find the value of $\frac{\tan ^2 30^{\circ}}{\sec ^2 30^{\circ}}+\frac{{cosec}^2 45^{\circ}}{\cot ^2 45^{\circ}}-\frac{\sec ^2 60^{\circ}}{{cosec}^2 60^{\circ}}$

$-\frac{3}{4}$

\(\frac{tan²30º}{sec²30º}\) + \(\frac{cosec²45º}{cot²45º}\) - \(\frac{sec²60º}{cosec²60º}\)

{ using , tanA = \(\frac{sinA}{cosA}\) , secA = \(\frac{1}{cosA}\) ,

cotA = \(\frac{cosA}{sinA}\) , cosecA = \(\frac{1}{sinA}\) }

= sin²30º + sec²45º - tan²60º

= \(\frac{1}{4}\) + 2 - 3

= - \(\frac{3}{4}\)