find the roots of the equation 3 x square - 5 x + 2 is equal to zero by the method of completing square
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Here given,
3x^2 - 5x + 2 = 0
(Multiplying the equation by 3, we get
9x^2 - 15x + 6 = 0
(3x)^2 - 2× (3x )×5/2 + (5/2)^2 = (5/2)^2 - 6
(3x - 5/2)^2 = 25/4 - 6
(3x - 5/2)^2 = (25 - 24)/4
(3x - 5/2)^2 = 1/4
3x - 5/2 = +1/2 and -1/2
3x = 5/2 + 1/2 or 5/2 - 1/2
3x = 6/2 or -4/2
3x = 3 or -2
x = 1 or -2/3.
So, 1 and -2/3 are the roots of the equation.
3x^2 - 5x + 2 = 0
(Multiplying the equation by 3, we get
9x^2 - 15x + 6 = 0
(3x)^2 - 2× (3x )×5/2 + (5/2)^2 = (5/2)^2 - 6
(3x - 5/2)^2 = 25/4 - 6
(3x - 5/2)^2 = (25 - 24)/4
(3x - 5/2)^2 = 1/4
3x - 5/2 = +1/2 and -1/2
3x = 5/2 + 1/2 or 5/2 - 1/2
3x = 6/2 or -4/2
3x = 3 or -2
x = 1 or -2/3.
So, 1 and -2/3 are the roots of the equation.
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