Answer:
x = 1/3 (sqrt(19) - 1) or x = (1/3 (-1 - sqrt(19)))
Step-by-step explanation:
Solve for x over the real numbers:
3 x^2 + 2 x - 6 = 0
Using the quadratic formula, solve for x.
x = (-2 ± sqrt(2^2 - 4×3 (-6)))/(2×3) = (-2 ± sqrt(4 + 72))/6 = (-2 ± sqrt(76))/6:
x = (-2 + sqrt(76))/6 or x = (-2 - sqrt(76))/6
Simplify radicals.
sqrt(76) = sqrt(4×19) = sqrt(2^2×19) = 2sqrt(19):
x = (2 sqrt(19) - 2)/6 or x = (-2 sqrt(19) - 2)/6
Factor the greatest common divisor (gcd) of -2, 2 sqrt(19) and 6 from -2 + 2 sqrt(19).
Factor 2 from -2 + 2 sqrt(19) giving 2 (sqrt(19) - 1):
x = 1/6(2 (sqrt(19) - 1)) or x = (-2 sqrt(19) - 2)/6
In (2 (sqrt(19) - 1))/6, divide 6 in the denominator by 2 in the numerator.
(2 (sqrt(19) - 1))/6 = (2 (sqrt(19) - 1))/(2×3) = (sqrt(19) - 1)/3:
x = (1/3 (sqrt(19) - 1)) or x = (-2 sqrt(19) - 2)/6
Factor the greatest common divisor (gcd) of -2, -2 sqrt(19) and 6 from -2 - 2 sqrt(19).
Factor 2 from -2 - 2 sqrt(19) giving 2 (-sqrt(19) - 1):
x = 1/3 (sqrt(19) - 1) or x = 1/6(2 (-1 - sqrt(19)))
In (2 (-sqrt(19) - 1))/6, divide 6 in the denominator by 2 in the numerator.
(2 (-sqrt(19) - 1))/6 = (2 (-sqrt(19) - 1))/(2×3) = (-sqrt(19) - 1)/3:
Answer: x = 1/3 (sqrt(19) - 1) or x = (1/3 (-1 - sqrt(19)))
