Question
The shadow of a pole on ground level is increased by 24
m when the angle of depression of the sun changes from 60° to 30°. What is the height of the pole?Solution
Tan 60° = h /x    h = √3x      … (1) Tan30° = h/(x+24) 1/√3 =h/x+24 h = (x+24)/√3     … (2) EQ (1) and Eq (2) both are equal. √3x =(x+24)/√3 3x =x+24 2x =24 X=12. Now put the value of x in equation (1). Height =12√3 m. 
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