Express the roots of the equation 3x^2 = -2 (x+3) in a+bi form.

问题描述:

Express the roots of the equation 3x^2 = -2 (x+3) in a+bi form.

3x^2 = -2 (x+3)
=> 3x^2 = -2x - 6
=> 3x^2 +2x + 6 = 0
roots = (-b+/-sqrt(b^2-4ac))/(2a)
(-2+sqrt(4-72))/6
= (-2+sqrt(-68)/6
= (-2+sqrt(-17*4)/6
= (-2+2*sqrt(17)i)/6
roots = -1/3 + 1/3*sqrt(17)*i
-1/3 - 1/3*sqrt(17)*i