The teacher will be very surprised to see your correct solution 😉
a*x^2 + b*x + c = 0
D = b^2 - 4 * a * c =
(-19)^2 - 4 * (-1) * (-105) = -59
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
sum
____ ____ 19 I*\/ 59 19 I*\/ 59 - -- - -------- + - -- + -------- 2 2 2 2
=
-19
product
/ ____\ / ____\ | 19 I*\/ 59 | | 19 I*\/ 59 | |- -- - --------|*|- -- + --------| \ 2 2 / \ 2 2 /
=
105
105
____ 19 I*\/ 59 x1 = - -- - -------- 2 2
____ 19 I*\/ 59 x2 = - -- + -------- 2 2
x2 = -19/2 + sqrt(59)*i/2
x1 = -9.5 + 3.8405728739343*i
x2 = -9.5 - 3.8405728739343*i
x2 = -9.5 - 3.8405728739343*i