If the ratio of the roots of the equation 4x 2 -6x p=0 is 1:2 then the...
Solution:
Given, the equation is 4x^2 - 6xp = 0
Let the roots of the equation be a and b such that a:b = 1:2
Ratio of roots of a quadratic equation
The ratio of the roots of the quadratic equation ax^2 + bx + c = 0 is (-b ± √(b^2 - 4ac))/2a
Therefore, a:b = (-(-6p) ± √((-6p)^2 - 4(4)(0)))/2(4)
Simplifying, we get 1:2 = (3p ± √(9p^2))/4
Squaring both sides, we get (1/4) = (9p^2)/16
Solving the above equation, we get p = ±2/3
But we need to find the value of p, which satisfies the given equation.
Substituting p = 2/3 in the given equation, we get 4x^2 - 4x = 0
Solving the above equation, we get x = 0, 1
Therefore, the roots of the equation are 0 and 1, and their ratio is 0:1, which is not equal to 1:2.
Substituting p = -2/3 in the given equation, we get 4x^2 + 4x = 0
Solving the above equation, we get x = 0, -1/4
Therefore, the roots of the equation are 0 and -1/4, and their ratio is 0:-1/4, which is equal to 1:2.
Hence, the value of p is -2/3.
Answer: c) -2
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