If x^4*y 0 which of the following must be true?

Question

Competition Mode Question If x^4*y < 0 and x*y^4 > 0 which of the following must be true? A. x > y B. y > x C. x = y D. x < 0 E. y > 0

Archit3110 · Answer

from given info
x^4∗y<0 and x∗y4>0
we know that x has to be +ve and y is -ve
in that case
x>y
IMO A

If x^4∗y<0 and x∗y4>0 which of the following must be true?

A. x>y
B. y>x
C. x=y
D. x<0
E. y>0

Stonely · Answer

If x^4∗y<0 and x∗y^4>0 which of the following must be true?

A. x>y
B. y>x
C. x=y
D. x<0
E. y>0

x^4∗y<0 negative y must be negative eliminating choices E
x∗y^4>0 pos x can't be negative eliminating choices D
Together eliminating choices C & B

only remaining is A

PTD1995 · Answer

x^4 * y < 0 -> y<0 , as a variable (that's not 0) powered to an even is greater than 0. Hence, x must be positive and y negative y^4 * x > 0 -> x>0 , same reasoning. Hence, x must be positive. Consequently, x > y Option A

freedom128 · Answer

The two inequalities simply mean that y<0 and x>0. Therefore it must be true that x>y.

Final answer is (A)

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Jawad001 · Answer

From the first information, x^4 ∗y<0
 x^4 is always positive
 y is negative.

From the second information, x∗y^4>0
 y^4 is always positive
 x is also positive.

From the above discussions, we can conclude as x>y (A)

unraveled · Answer

If x^4∗y<0 and x∗y^4>0 which of the following must be true? A. x>y B. y>x C. x=y D. x<0 E. y>0 x^4∗y<0 suggests y < 0 AND x∗y^4>0 suggests that x > 0 So, x > y Answer A.

eakabuah · Answer

If x^4 * y < 0, then we conclude that y<0, since irrespective of the value of x, x^4 will be positive, hence for x^4 * y to be negative, then y<0.
y^4 * x > 0, then we can conclude that x>0, since irrespective of the value of y, y^4 > 0, hence x>0 for y^4 * x > 0.

Scanning through the answer choices, only A x>y must be true because a positive number is greater than a negative number.

The answer is A.

ostrick5465 · Answer

x^{4}∗y<0 => y<0, x eq{0} x∗y^{4}>0 => x>0 => x>y => Choice A

bumpbot · Answer

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If x^4y < 0 and xy^4 > 0 which of the following must be true?

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If x^4*y < 0 and x*y^4 > 0 which of the following must be true?