The angle of elevation of to be top point `P` of the vertical tower PQ of height `h` from poin A is `45^0` and from a point B, the angle of elevation is `60^0,` where B is point at a distance `d` from the point A measured along the line `A B` which makes an angle `30^0` with AQ. Prove that `d=(sqrt(3)-1)hdot`

Explanation

`cosc=(a^2+b^2-c^2)/(2ab)`

`=(7^2+8^2-9^2)/(2*7*8)`

`=2/7`

`BM^2=BC^2+CM^2-2BC*CM*cosc`

`=7^2+4^2-2*7*4*2/7`

`=49`

`BM=7`

`In/_BMP`

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