canbtg wrote:if x is not equal to 0, is -4/X^3 negative ?
1)x is positive
2)X^3-x^2 is positive
OAD
A very useful strategy:
When x≠0, we can safely divide each side of an inequality by x², which must be equal to a POSITIVE value.
Is (-4)/x³ < 0?
Since negative/positive = negative, (-4)/x³ < 0 only if x³ > 0.
Dividing each side of x³ > 0 by x², we get:
x³/x² > 0/x²
x > 0.
Question rephrased:
Is x > 0?
Statement 1: x > 0
SUFFICIENT.
Statement 2: x³ - x² > 0
x³ > x²
x³/x² > x²/x²
x > 1.
SUFFICIENT.
The correct answer is
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