If x < 0, which of the following must be true?I. x2 > 0II. x &mi...
To determine which of the given statements must be true when x < 0, let's examine each statement individually:
I. x2 > 0:
For any real number x, squaring it will always result in a non-negative value (greater than or equal to zero). However, since x < 0 in this case, x^2 will be positive. Therefore, statement I is true.
II. x − 2x > 0:
Simplifying the expression, we get -x > 0. Since x < 0, multiplying both sides of the inequality by -1 flips the sign, giving us x < 0, which is true. Therefore, statement II is true.
III. x3 + x2 < 0:
Substituting x = -1 into the expression, we get (-1)3 + (-1)2 = -1 + 1 = 0. Since the expression evaluates to zero, it is not less than zero. Therefore, statement III is false.
Based on our analysis, statements I and II are true, while statement III is false. Thus, the correct answer is (B) I & II.