ds: inequality: GMATprep

Question

although III appears correct, I cannot deduce it mathematically..

paddyboy · Answer

E is the answer. I and II are evident. III: Take x = 1/k (k>1 since 01; Hence statement III is true as well.

ayb7768 · Answer

another way to prove that III must also be true is to factor it out: X^4 - X^5 < X^2 - X^3 -> X^4 (1- X) < X^2 (1-X) -> X^2 < 1 Which must be true as well since 0

haas_mba07 · Answer

Answer: E 

If you notice all three statements eventual degenerate to x^2 < 1 inequality.

With 0 < x < 1, this remains is true.
Therefore, I, II, & III.

Answer: E.

Raghavender · Answer

Gud explanation dude...I did tht by directly substituting 0.1 in the options...u can jus c them, observe the values and go for E

jaynayak · Answer

Easy E.

Just put x = 1/2
And you will get the answers.

ps_dahiya · Answer

you got I and II. Here is III: X^4 - X^5 < X^2 - X^3 ===> X^4(1-X) < X^2(1-X) ===> X^2<1 : TRUE

ywilfred · Answer

x is a positive fraction.

so x^5 True

x^4 + x^5 True

x^4 - x^5 True

Ans: E

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