Question

first bracket sin thita/cos thita + cos thita/sin thita bracket close then whole square =?

Answer 1

$( \frac{ \sin( \alpha ) }{ \cos( \alpha ) } \times \frac{ \cos( \alpha ) }{ \sin( \alpha ) } ) {}^{2} \\ \\ = ( \frac{ \sin( \alpha ) \sin( \alpha ) + \cos( \alpha ) \cos( \alpha ) }{ \sin( \alpha ) \cos( \alpha ) } ) {}^{2} \\ \\ ( \frac{ \sin {}^{2} ( \alpha ) + \cos {}^{2} ( \alpha ) }{ \sin( \alpha ) \cos( \alpha ) } ) {}^{2} \\ \\ = ( \frac{1}{ \sin( \alpha ) \cos( \alpha ) } ) {}^{2} \\ \\ = ( \frac{2}{2 \sin( \alpha ) \cos( \alpha ) } ) {}^{2} \\ \\ = ( \frac{2}{ \sin(2 \alpha ) } ) {}^{2} \\ \\ = \frac{4}{ \sin {}^{2} (2 \alpha ) } \\ \\ = 4 \cosec {}^{2} (2 \alpha )$


Hope it helps...