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by aatech » Wed May 14, 2008 1:05 pm
ANS 15

Here its goes

2^[x-2] can be written as [2^x]/[2^2].

Now, solve the eq given in question

LHS = [2^x]-[[2^x]/[2^2]] = [2^x][1-1/4] = 3*[2^x]/4 = 3*[2^x-2]

RHS = 3*2^13

Equate LHS and RHS

x-2=13

so, x = 15
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by vinviper1 » Thu May 15, 2008 11:01 am
Thanks.

Another way that I have figured out with the help of this forum:
Factor out 2^x-2

You get 2^x-2( 2^2 - 1) = 3(2^13)

2^x-2( 3) = 3(2^13)

x = 15
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