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If a = "log"2, b = "log" 3, c ="log" 7 "...

If `a = "log"2, b = "log" 3, c ="log" 7 " and " 6^(x) = 7^(x+4)` then x=

A

`(4b)/(c+a-b)`

B

`(4c)/(a+b-c)`

C

`(4b)/(c-a-b)`

D

`(4a)/(a+b-c)`

Text Solution

Verified by Experts

The correct Answer is:
B
We have,
`6^(x) = 7^(x+4)`
`rArr x "log" 6 = (x+4)"log" 7`
`rArr x = (4"log"7)/("log"6-"log"7) = (4"log"7)/("log"2 + "log"3-"log"7) = (4c)/(a+b-c)`
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