Advertisements
Advertisements
प्रश्न
For the equation given below, find the value of ‘m’ so that the equation has equal roots. Also find the solution of the equation:
3x2 + 12x + (m + 7) = 0
Advertisements
उत्तर
3x2 + 12x + (m + 7) = 0
Here a = 3, b = 12 and c = m + 7
Given equation has equal roots
Then D = 0
`=>` b2 – 4ac = 0
`=>` (12)2 – 4(3)(m + 7) = 0
`=>` 144 – 12m – 84 = 0
`=>` – 12m = – 60
`=>` m = 5
Put value of m in given equation
3x2 – 12x + 12 = 0
`=>` x2 + 4x + 4 = 0
`=>` (x + 2)2 = 0
`=>` x + 2 = 0
`=>` x = – 2
APPEARS IN
संबंधित प्रश्न
Solve for x : 12abx2 – (9a2 – 8b2 ) x – 6ab = 0
A two digits number is such that the product of the digits is 12. When 36 is added to the number, the digits inter change their places determine the number.
A plane left 40 minutes late due to bad weather and in order to reach its destination, 1600 km away in time, it had to increase its speed by 400 km/hr from its usual speed. Find the usual speed of the plane.
Solve the following quadratic equation for x:
`4sqrt3x^3+5x-2sqrt3=0`
If \[x = - \frac{1}{2}\],is a solution of the quadratic equation \[3 x^2 + 2kx - 3 = 0\] ,find the value of k.
If one root of the equation 4x2 − 2x + (λ − 4) = 0 be the reciprocal of the other, then λ =
The side (in cm) of a triangle containing the right angle are 5x and 3x – 1. If the area of the triangle is 60 cm². Find the sides of the triangle.
Solve the following equation by factorization:
`x^2 - (1 + sqrt(2))x + sqrt(2) = 0`
Solve the following equation by factorisation :
`sqrt(x + 15) = x + 3`
Find the roots of the following quadratic equation by the factorisation method:
`2x^2 + 5/3x - 2 = 0`
