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Solve the equation
4x^2-4x-1=0

User Deepak
by
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1 Answer

6 votes

Answer:

x = (1 ±√2)/2

Explanation:

We can "complete the square" to solve this.

4x^2 -4x = 1 . . . . add 1

x^2 -x = 1/4 . . . . .divide by 4 to make x^2 coefficient = 1

x^2 -x +1/4 = 2/4 . . . . add the square of half the x-coefficient: (-1/2)^2 = 1/4

(x -1/2)^2 = 2/4 . . . . write as a square

x -1/2 = ±(√2)/2 . . . . . take the square root

x = (1 ±√2)/2 ≈ {-0.2071, 1.2071}

Solve the equation 4x^2-4x-1=0-example-1
User Danyo
by
3.2k points