If the angle of a h meters long tower is in a straight line between two observers A and B angle of elevation of the top of the tower from A and B are alpha and beta respectively and AB=D meters find h/d

2 answers

say d = x + y
tan alpha = h/x
tan beta = h/y

so x = h/tan alpha
and y = h/tan beta

d = x + y = h (1/tan alpha + 1/tan beta)
or
d = h (cot alpha + cot beta)
h/d = 1/(cot alpha + cot beata)
Tnx damon