x^2 + x + 2 is not factorable using rational numbers. This means that no rational numbers added together equal 1 (x in equation) and multiplied together equal 2.
You can find the imaginary answer to x^2 + x + 2 = 0 (an equation, notice the =), however.
Using the quadratic formula: (-b+-sqrt(b^2-4ac))/(2a)
x would then equal (-1 +- isqrt(7))/2
and the factors would be x^2+x+2 = (x+(1+sqrt(7)i)/2)(x+(1-sqrt(7)i)/2)