Question

An eagle is sitting on the top of a tower, which is 80m high. the angle of elevation of the eagle from a point on the ground is 45°. th eagle flies away from the point of observation horizontally and remains at a constant height. after 2 seconds, the angle of elevation of the eagle from the point of observation become 30°. find the speed of flying the eagle.

Answer 1

triangle OAC tan 45=AC/OA=1

AC=OA=80

IN TRIANGLE ODB

tan 30=BD/OB=1/√ 3

OB=BD√ 3-AC√ 3(since ac=bd as bird remains constant height)

AB=OB-OA=AC√ 3-AC=AC(√ 3-1)=80(√ 3-1)

NOW FOR 2 SEC

80(√ 3-1)/2=

40(√3-1)is the answer. ....

Answer 2

here is ur answer buddy..........