Advertisements
Advertisements
प्रश्न
Find the length of the tangent from (1, 2) to the circle x2 + y2 – 2x + 4y + 9 = 0.
उत्तर
The length of the tangent from (x1, y1) to the circle x2 + y2 – 2x + 4y + 9 = 0 is `sqrt(x_1^2 + y_1^2 - 2x_1 + 4y_1 + 9)`
Length of the tangent from (1, 2) = `sqrt(1^2 + 2^2 - 2(1) + 4(2) + 9)`
`= sqrt(1 + 4 - 2 + 8 + 9)`
`= sqrt20`
`= sqrt(4 xx 5)`
`= 2sqrt5` units
APPEARS IN
संबंधित प्रश्न
Find the equation of the circle on the line joining the points (1, 0), (0, 1), and having its centre on the line x + y = 1.
Find the value of P if the line 3x + 4y – P = 0 is a tangent to the circle x2 + y2 = 16.
Obtain the equation of the circles with radius 5 cm and touching x-axis at the origin in general form
A circle of area 9π square units has two of its diameters along the lines x + y = 5 and x – y = 1. Find the equation of the circle
If y = `2sqrt(2)x + "c"` is a tangent to the circle x2 + y2 = 16, find the value of c
Find the equation of the tangent and normal to the circle x2 + y2 – 6x + 6y – 8 = 0 at (2, 2)
Find centre and radius of the following circles
x2 + y2 + 6x – 4y + 4 = 0
Find centre and radius of the following circles
x2 + y2 – x + 2y – 3 = 0
Choose the correct alternative:
The equation of the circle passing through (1, 5) and (4, 1) and touching y-axis `x^2 + y^2 - 5x - 6y + 9 + lambda(4x + 3y - 19)` = where `lambda` is equal to
Choose the correct alternative:
If the normals of the parabola y2 = 4x drawn at the end points of its latus rectum are tangents to the circle (x – 3)2 + (y + 2)2 = r2, then the value of r2 is
