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Find the roots of the following quadratic equations, if they exist, by the method of completing the square: (i) 4x^2 + 4√3x + 3 = 0 (ii) 2x^2 + x + 4 = 0

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Find the roots of the following quadratic equations, if they exist, by the method of completing the square:

(i) 4x2 + 4√3x + 3 = 0

(ii) 2x2 + x + 4 = 0

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(i) 4x2 + 4√3x + 3 = 0

Converting the equation into a2+2ab+bform, we get,

⇒ (2x)2 + 2 × 2x × √3 + (√3)2 = 0

⇒ (2x + √3)2 = 0

⇒ (2x + √3) = 0 and (2x + √3) = 0

Therefore, either x = -√3/2 or x = -√3/2.

(ii) 2x2 + x + 4 = 0

⇒ 2x2 + x = -4

Dividing both sides of the equation by 2, we get

⇒ x2 + 1/2x = 2

⇒ x2 + 2 × x × 1/4 = -2

By adding (1/4)to both sides of the equation, we get

⇒ (x)+ 2 × x × 1/4 + (1/4)2 = (1/4)– 2

⇒ (x + 1/4)2 = 1/16 – 2

⇒ (x + 1/4)2 = -31/16

The square of numbers cannot be negative.

Therefore, there is no real root for the given equation, 2x2 + x + 4 = 0.

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