If tan θ +sec θ =l, then prove that sec θ =

A vertical tower stands on a horizontal plane and is surmounted by a vertical flag staff of height h. At a point on the plane, the angles of elevation of the bottom and the top of the flag staff are α and β respectively. Prove that the height of the tower is .

If tan θ +sec θ =l, then prove that sec θ =

If sin θ +cos θ =p and sec θ +cosec θ =q, then prove that q(p² - 1)=2p.

If sin θ +cos θ =p and sec θ +cosec θ =q, then prove that q(p² - 1)=2p.