Question

From the top of a cliff,60 metres high, the angles of depression of the top and bottom of a tower are observed to be 30 ° and 60 °.Find the height of the tower.

Answer 1

I can't understand..

Answer 2

\[\tan\theta = \frac{\text{opp}}{\text{adj}}\]

Answer 3

Let AB be the building h meters high, and PQ be the tower 60 m high situated at distance BQ = x meters away.
Then AC = BQ = x, CQ = AB = h,
PC = 60 -h
From BPQ, cot 60° = BQ/PQ = x/60
=> x = 60 cot 60°
From APC, cot 30° = AC/PC = x/(60 -h)
=> 60 -h = x/ cot 30° = 60 cot 60° tan 30° = 60 (1/3)(1/3) = 20
=> h = 60 -20 = 40
Thus the building is 40 meters high and is situated 34·64 meters away from the tower.

Answer 4

i've given you the figure pls refer to it

Answer 5

^^^^ i think the use of inverse trigonometric functions is unnecessary.

Answer 6

no by cot theta it is helpful and cot theta is just the opposite of tan theta

Answer 7

Yes, but I don't think this person has actually learnt inverse trigonometry, and for the sake of simplicity I don't think he/she needs to know it for now.