Respuesta :

[tex]\frac{cot^2x -cosec\ x}{cosec^2x} = cos^2x - sin\ x[/tex]

Solution:

Given that we have to prove:

[tex]\frac{cot^2x -cosec\ x}{cosec^2x} = cos^2x - sin\ x[/tex]

Take the L.H.S of above

[tex]\frac{cot^2x -cosec\ x}{cosec^2x}[/tex]

Simplify

[tex]\frac{cot^2x}{cosec^2x} -\frac{cosec\ x}{cosec^2x}\\\\Simplify\\\\\frac{cot^2x}{cosec^2x} -\frac{1}{cosec\ x}[/tex]

We know that,

[tex]sin\ x = \frac{1}{cosec\ x}[/tex]

Therefore,

[tex]\frac{cot^2x}{cosec^2x} -sin\ x[/tex]

Also we know that,

[tex]cot^2x = \frac{cos^2\ x}{sin^2\ x}[/tex]

[tex]cosec^2\ x = \frac{1}{sin^2\ x}[/tex]

Thus we get,

[tex]\frac{\frac{cos^2\ x}{sin^2 x}}{\frac{1}{sin^2\ x}} - sin\ x\\\\Simplify\\\\\frac{cos^2\ x}{sin^2 x} \times sin^2\ x - sin x\\\\Simplify\\\\cos^2\ x - sin\ x[/tex]

Thus,

L.H.S = R.H.S

Thus proved