Question by Đỗ Phi Phi - Discuss with MathYouLike

Đỗ Phi Phi

08/01/2018 at 21:28

If 0< a< b< 1. which of the following is (are) true?

I. a- b is negative

II. \(\dfrac{1}{ab}\) is positive

III. \(\dfrac{1}{b}\) - \(\dfrac{1}{a}\) is positive

(A) I only (B) II only (C) III only (D) I and II only (E) I, II and III

Fraction Grade 6 Numbers

List of answers

FA Liên Quân Garena 08/01/2018 at 21:40

I chose the answer : E
Yuki Judai 20/01/2018 at 06:50

hjh.hj.kjh,jhb,bjv,
Trương Như Hoàng 08/01/2018 at 22:22

I choose D because :
a<b => a-b<0 which means a-b is negative so I is true.

0<a<b => ab>0 => \(\dfrac{1}{ab}\) is positive so II is true.

\(\dfrac{1}{b}\) -\(\dfrac{1}{a}\)=\(\dfrac{a-b}{ab}\) but a-b<0 and ab>0 => \(\dfrac{a-b}{ab}\) is negative so III is false

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