Question
From a point situated at some distance from the base of
a pillar, the angle of elevation of the top of the pillar is found to be 45 degrees. After walking 12 m further, the value of elevation angle becomes 60 . Tell the height of the pillar.Solution
tan60=h/x √3= h/x x= h/√3 …. (1) When the angle of elevation becomes 45° tan45= h/(x+12) 1 = h/(h/(√3)+12) 1 = (√3h)/(h+12√3) √3h=h+12√3 √3h-h=12√3 h(√3-1)=12√3 h = (12√3)/(√3-1) 
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