Answer:
Step-by-step explanation:
The only way in which you can truly simplify this is to factor the quantity within parentheses. Use the quadratic formula for this purpose:
y^2 - 2y + 4 has coefficients {1, -2, 4}. The discriminant is b^2 - 4ac, which here is (-2)^2 - 4(1)(4), or 4 - 16, or -12. Since the discriminant is negative, we know that the roots of this quadratic are complex, different:
-b ± i√(discriminant)
y = ---------------------------------
2a
-(-2) ±i√12 2 ±i2√3)
Then y = ------------------- = ---------------- = 1 ±i√3
2 2
and we end up with these three factors: x, x - 1 +i√3, x - 1 -i√3
So the original expression becomes -3·y·(y-1i√3)(y - 1 -i√3)
