Find all complex solutions of 3x^2+6x+1=0. (If there is more than one solution, separate them with commas.)

Use the quadratic formula:

for equation Ax^2+Bx+C=0

x = (-b + / - sqrt (b^2-4ac)) / 2a

substituting,

= (6 + / - sqrt (6^2-4*3*1)) / (2*3)

= (6 + / - 0) 6

=1 multiplicity 2. (both real)

If the complex form is required, then

{1+0i, multiplicity 2}