中等MATH-FUNC-004
How many x-intercepts does y = x^2 + 2x + 3 have?
A. 0✓ 答案
B. 1
C. 2
D. 3
解說
The discriminant is 4 − 12 = −8 < 0, so the equation y = 0 has no real root. The parabola opens upwards and stays above the x-axis.
The discriminant is 4 − 12 = −8 < 0, so the equation y = 0 has no real root. The parabola opens upwards and stays above the x-axis.