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HPengineer
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IMO CHPengineer wrote:If pq ≠0, is p2q > pq2?
(1) pq < 0
(2) p < 0
Love to see some other ways to work this one..
Rephrasing the question -
Given, pq <> 0 ,
p^2 * q > p * q^2 ?
p (pq) > q (pq) ?
Dividing both sides by pq (since we are given pq is not zero)
p > q? So this is the question
1) pq < 0
This means p and q both have opposite signs, but we dont know p < q or q < p, not sufficient.
2) p < 0
we dont know anything about q, Not sufficient.
1) & 2)
we know that p < 0, so according to 1) q has to be > 0, hence we know that p > q is not true. Hence Sufficient.
















