CAT - Logarithms


Question:
If log2X + log4X = log0.25and x > 0, then x is
A.  6-1/6
B.  61/6
C.  3-1/3
D.  61/3

Correct Answer: (A)

Explanation:

log2x + log4x = log0.25

log2x + = log0.25

log2x * = log0.25

log2x * 3 = 2log0.25

log2x3 = log0.256

log2x3 = -log46

log2x3 =

log2x3 =

2log2x3 = -log26

2log2x3 + log26 = 0

log26x6 = 0

6x6 = 1

x6 =

x =  Choice (A).

Level of difficulty 2

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IIM CAT Preparation Tips: CAT - Logarithms

Aug 12, 2013

CAT - Logarithms


Question:
If log2X + log4X = log0.25and x > 0, then x is
A.  6-1/6
B.  61/6
C.  3-1/3
D.  61/3

Correct Answer: (A)

Explanation:

log2x + log4x = log0.25

log2x + = log0.25

log2x * = log0.25

log2x * 3 = 2log0.25

log2x3 = log0.256

log2x3 = -log46

log2x3 =

log2x3 =

2log2x3 = -log26

2log2x3 + log26 = 0

log26x6 = 0

6x6 = 1

x6 =

x =  Choice (A).

Level of difficulty 2

Labels: , , , , , ,

3 Comments:

At 11:09 AM , Blogger Freblogg said...

good one

 
At 10:08 PM , Blogger Unknown said...

Yup really

 
At 10:08 PM , Blogger Unknown said...

Yup good one

 

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