3x2+x+1=0

2 answers

since it's not factorable, we use quadratic formula:
x = [-b +- sqrt(b^2 -4ac)]/(2a)
where a=3, b=1, and c=1
substituting:
x = [-1 +- sqrt(1^2 - 4*3*1)]/(2*3)
x = [-1 +- sqrt(-11)]/6
thus
x = [-1 + i*sqrt(11)]/6 ; and
x = [-1 - i*sqrt(-11)]/6
*note: i = sqrt(-1)

hope this helps~
oops, some typo:
x = [-1 + i*sqrt(11)]/6 ; and
x = [-1 - i*sqrt(11)]/6