Mathematics
The angle of elevation of a cloud from a point h metres above the surface of a lake is θ and the angle of depression of its reflection in the lake is Φ. Prove that the height of the cloud above the lake surface is : .
Related Questions
If two pipes function simultaneously, the reservoir will be filled in 12 hours. One pipe fills the empty reservoir 10 hours faster than the other. How many hours does it take the second pipe to fill the reservoir ?
The marks of 200 students are as given below :
Marks No. of students 20-29 7 30-39 11 40-49 20 50-59 46 60-69 57 70-79 37 80-89 15 90-99 7 Draw a cumulative frequency curve and find :
(i) median marks
(ii) if 80% of the students passed, find the passing marks.
Using ruler and compasses only construct
(i) a triangle ABC in which angle ABC = 45°, AB = 8.6 cm and BC = 9.8 cm
(ii) construct a circle of radius 2.5 cm which touches the arms of the angle BAC of △ABC given above.