I would approach this by plugging values... Since it is stated that x is negative, we can easily narrow down our test values...
Test for (1):
if x = -2 , (1) not true
if x = -4 , (1) stands when X < -3.
Therefore (1) is sufficient
Test for (2):
If x = -2 , (2) -8 is NOT less than -9, therefore not true
If x = -4 , (2) -64 IS less than -9, therefore (2) stands when x < -3.
Therefore (2) is sufficient
If we go back to the earlier question, is x < -3? Both statement (1) & (2) leads to X being LESS than -3, so the answer should be (D).
X is negative
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abhimanyu.tanwar
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(1) for x^2 = 9, x has to be 3
for x^2 > 9, x > 3 or x < -3, as it is already given in the question that x is negative, x^2 can only be greater than 9 when x < -3
SUFFICIENT
(2) it is nowhere given that x is an integer, even for x = -2.5 will give us a value -15.625 which is less than -9.
hence this is not sufficient.
for x^2 > 9, x > 3 or x < -3, as it is already given in the question that x is negative, x^2 can only be greater than 9 when x < -3
SUFFICIENT
(2) it is nowhere given that x is an integer, even for x = -2.5 will give us a value -15.625 which is less than -9.
hence this is not sufficient.
Regards
Abhimanyu
Abhimanyu
fsutanto,
thanks for your response, by picking numbers -it became clear to me. However, the OA is A and here is an explanation:
for statement 2: x^3 < -9
assume x = -4
statement 2: -64 < -9 YES
now going back to original question, is -4 < -3? YES
assume x = -3
statement 2: -27 < -9 YES
now going back to original question, is -3 < -3? NO
So therefore, statement 2 is NOT sufficient but statement 1 is SUFFICIENT.
Answer is A
thanks for your response, by picking numbers -it became clear to me. However, the OA is A and here is an explanation:
for statement 2: x^3 < -9
assume x = -4
statement 2: -64 < -9 YES
now going back to original question, is -4 < -3? YES
assume x = -3
statement 2: -27 < -9 YES
now going back to original question, is -3 < -3? NO
So therefore, statement 2 is NOT sufficient but statement 1 is SUFFICIENT.
Answer is A
