Question

If the angle of elevation of a cloud from a point h metres above a lake is alpha and the angle of depression of itr reflection in tha lake its beta, prove thay the height of the cloud is h(tan beta + tan alpha) / tan beta - tan alpha.

Answer 1

continued from the picture.....
CB= x+h
CB= 2h(tan alpha) / (tan beta-tan alpha). +h
CB= (2h tan alpha +h tan beta -h tan alpha) / (tan beta - tan alpha)
CB= {(tan alpha+ tan beta)} / tan beta - tan alpha.