If the equation x ^ 2 + MX + 1 = 0 of X has two unequal real roots, the value range of real number m is as follows: A. (- 1,1) B, (- 2,2) C, (negative infinity, - 2) ∪ (2, positive infinity) d, (negative infinity, - 1) ∪ (1, positive infinity)

If the equation x ^ 2 + MX + 1 = 0 of X has two unequal real roots, the value range of real number m is as follows: A. (- 1,1) B, (- 2,2) C, (negative infinity, - 2) ∪ (2, positive infinity) d, (negative infinity, - 1) ∪ (1, positive infinity)

The equation x ^ 2 + MX + 1 = 0 of X has two unequal real roots
b²-4ac=m²-4>0
(m+2)(m-2)>0
| m < - 2 or m > 2
Choose C, (negative infinity, - 2) ∪ (2, positive infinity)