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Solve the equation 3x2 + 6x - 2 = 0

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Solve the equation 3x2 + 6x - 2 = 0

A.

x = -1 \(\pm\) \(\frac{\sqrt{3}}{3}\)

B.

x = -1 \(\pm\) \(\frac{\sqrt{15}}{3}\)

C.

x = -2 \(\pm\) 2

D.

x = 3 \(\pm\) \(\frac{\sqrt{3}}{15}\)

Correct answer is B

3x2 + 6x - 2 = 0

Using almighty formula i.e. x = \(\frac{b \pm \sqrt{b^2 - 4ac}}{2a}\)

a = 3, b = 6, c = -2

x = \(\frac{-6 \pm \sqrt{6^2 - 4(3)(-2)}}{2(3)}\)

x = \(\frac{-6 \pm \sqrt{36 + 24}}{6}\)

x = \(\frac{-6 \pm \sqrt{60}}{6}\)

x = \(\frac{-6 \pm \sqrt{4 \times 15}}{6}\)

x = \(-1 \pm \frac{\sqrt{15}}{3}\)