Advertisements
Advertisements
प्रश्न
Find the distance between the points (a, b) and (−a, −b).
उत्तर
Using distance formula:
`d = sqrt((x_2 - x_1)^2 + (y_2 - y_1)^2)`
Here, x1 = a, y1 = b, x2 = -a and y2 = -b
On substituting the values in the formula we get
`sqrt((-a - a)^2 + (-b-b)^2)`
= `sqrt((-2a)^2 + (-2b)^2)`
=`sqrt(4a^2 + 4b^2)`
= `2sqrt(a^2 + b^2)`
Therefore, the distance between (a,b) and (-a,-b) is `2sqrt((a^2) + (b^2))`
APPEARS IN
संबंधित प्रश्न
The angles of elevation and depression of the top and the bottom of a tower from the top of a building, 60 m high, are 30° and 60° respectively. Find the difference between the heights of the building and the tower and the distance between them.
An aeroplane flying horizontally 1 km above the ground is observed at an elevation of 60°. After 10 seconds, its elevation is observed to be 30°. Find the speed of the aeroplane in km/hr.
The angle of elevation of an aeroplane from a point on the ground is 45° after flying for 15seconds, the elevation changes to 30° . If the aeroplane is flying at a height of 2500 meters, find the speed of the areoplane.
From a point on a bridge across a river, the angles of depression of the banks on opposite sides of the river are 30° and 45° respectively. If the bridge is at a height of 2.5m from the banks, find the width of the river.
From the top of a lighthouse, an observer looking at a ship makes angle of depression of 60°. If the height of the lighthouse is 90 metre, then find how far the ship is from the lighthouse.
A ladder 15 m long just reaches the top of a vertical wall. If the ladder makes an angle of 60° with the wall, then the height of the wall is
The upper part of a tree is broken by the wind and makes an angle of 30° with the ground. The distance from the foot of the tree to the point where the top touches the ground is 5 m. The height of the tree is ____________.
The angle of elevation of the top of a building from the foot of the tower is 30° and the angle of elevation of the top of the tower from the foot of the building is 60°. If the tower is 60 m high, find the height of the building.
If the length of the shadow of a tower is increasing, then the angle of elevation of the sun ____________.
An observer 1.5 metres tall is 20.5 metres away from a tower 22 metres high. Determine the angle of elevation of the top of the tower from the eye of the observer.