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Question
Solve by completing the square:
4x2 − 3 = 2x
Sum
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Solution
Given:
4x2 − 3 = 2x
Bring all terms to one side
4x2 − 2x − 3 = 0
Divide the entire equation by 4:
`x^2 - 1/2 x - 3/4 = 0`
`x^2 - 1/2 x = 3/4`
Complete the square
Coefficient of x = `-1/2`
Half = `-1/4`
Square = `(1/4)^2 = 1/16`
`x^2 - 1/2x +1/16 = 3/4 + 1/16`
`3/4 = 12/16`
`=> 12/16 + 1/16 = 13/16`
`(x-1/4)^2 = 13/16`
`x - 1/4 = +- sqrt(13/16) = +-sqrt13/4`
`x = 1/4 +- sqrt13/4`
`x = (1+sqrt13)/4 or x = (1-sqrt13)/4`
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