Which of the following inequalities has a solution set of ?
A:
B:
C:
D:
Which of the following inequalities has a solution set of ?
A:
B:
C:
D:
To analyze the solution sets of the given inequalities, we need to check the discriminant and the coefficient of to determine the nature of the roots and consequently, the solution set of each inequality.
### Option A:
1. Calculate the discriminant: .
2. Since and the coefficient of (which is ) is positive, the parabola opens upwards and does not intersect the x-axis. Therefore, the inequality holds for all real numbers.
.
### Option B:
1. Calculate the discriminant: .
2. Since , the equation has a double root: .
3. The parabola opens upwards (coefficient of is positive), touching the x-axis at one point. Hence, it is positive for all except at .
.
### Option C:
1. Calculate the discriminant: .
2. Since and the coefficient of (which is ) is negative, the parabola opens downwards and does not intersect the x-axis. Therefore, the inequality holds for all real numbers.
.
### Option D:
1. Calculate the discriminant: .
2. Since , the equation has two distinct real roots: .
3. As the parabola opens upwards (coefficient of is positive), the inequality holds between the roots.
.
Therefore, considering the analysis above, the correct options are .