Answer:
[tex] \frac{ { \sin}^{2} y}{ { \sec}^{2}y - 1 } = { \cos }^{2} y[/tex]
Step-by-step explanation:
We know that [tex] { \tan }^{2} y = { \sec }^{2} y - 1[/tex]
Also , [tex] { \tan}^{2} y = \frac{ { \sin }^{2} y}{ { \cos }^{2}y } [/tex]
So ,
[tex] \frac{ { \sin }^{2}y }{ { \sec }^{2}y - 1 } = \frac{ { \sin}^{2} y}{ { \tan }^{2} y} = \frac{ { \sin }^{2}y }{ \frac{ { \sin}^{2} y}{ { \cos}^{2}y } } = { \cos }^{2} y[/tex]
