Q) In the given figure AC is the diameter of the circle with centre O. CD is parallel to BE. angle AOB = 80 deg and angle ACE = 20 deg . Calculate: (a) angle BEC (b) angle BCD (c) angle CED Ans: (a) ∠ BEC: Step 1: Given that ∠ AOB = 800 ∠ […]
trigonometry applications
Q) From a point on a bridge across the river, the angles of depressions of the banks on opposite sides of the river are 30° and 60° respectively. If the bridge is at a height of 4 m from the banks, find the width of the river. Ans: Let’s start with a diagram for this
From a point on a bridge across the river, the angles of depressions of the banks Read More »
Q) The angles of depression of the top and the bottom of a 8 m tall building from the top of a multi-storeyed building are 30° and 45° respectively. Find the height of the multi-storeyed building and the distance between the two buildings. Ans: Step 1: Let’s start with the diagram for this question: Here
Q) A moving boat is observed from the top of a 150 m high cliff moving away from the cliff. The angle of depression of the boat changes from 60° to 45° in 2 minutes. Find the speed of the boat in m/h. Ans: Step 1: Let’s start with the diagram for this question: Here,
A moving boat is observed from the top of a 150 m high cliff moving away from the cliff. Read More »
Q) The angle of elevation of a cloud from a point h metres above a lake is α and the angle of depression of its reflection in the lake is β, prove that the distance of the cloud from the point of observation is . Ans: Step 1: Let’s draw a diagram for the given
Q) From an aeroplane vertically above a straight horizontal road, the angles of depression of two consecutive mile stones on opposite sides of the aeroplane are observed to be α and β. Show that the height in miles of aeroplane above the road is given by tan α tan ẞ / (tan α + tan
From an aeroplane vertically above a straight horizontal road, the angles of depression Read More »
Q) From the top of a light house, the angles of depression of two ships on the opposite sides of it are observed to be a and ẞ. If the height of the light house be h metres and the line joining the ships passes through the foot of the light house, show that the
Q) An observer 1.5 m tall is 28.5 m away from a tower and the angle of elevation of the top of the tower from the eye of the observer is 45 degrees. What is the height of the tower? Ans: Step 1: Let’s draw a diagram for the given question: Let the tower be
Q) An observer 1.5 m tall is 28.5 m away from a 30 m high tower. Determine the angle of elevation of the top of the tower from the eye of the observer. Ans: Step 1: Let’s draw a diagram for the given question: Let the tower be AB and observer be CD. We need
Q) The angles of depression of the top and the bottom of a 50 m high building from the top of a tower are 45° and 60°, respectively. Find the height of the tower. (Use √3 = 1·73) Ans: Let’s start with the diagram for this question: Here we have tower AB is the tower
The angles of depression of the top and the bottom of a 50 m high building from the Read More »