Question

If log_2x+log_4x+log_16x=21/4 then x is equal to

Answer 1

Solution :

Log ( 2x ) + log ( 4x ) + log ( 16x ) = 21/4

Identity :

We know that :

Log (a) + log (b) + log (c) = log ( abc )

Implementing this here ;

Log ( 128 x³ ) = 21/4

Identity :

We know that :

log (ab ) = log (a) + log (b)

log 128 + log x³ = 21/4

=> log 2^7 + log x³ = 21/4

=> 7 log 2 + 3 log x = 21/4

Now ,

log 2 ≈ 0.3010

=> 7 × 0.3010 + 3 log x = 5.25

=> 2.107 + 3 log x = 5.25

=> 3 log x = 3.143

=> log x ≈ 1.0476

=> x = 10¹.⁰⁴⁷⁶

This is the required answer .

________________________________

Answer 2

Answer:

it may be logx base 2...not log 2x..if it is then the ans is x=8..if not pls let me know