If 2^x - 2^x-2=3(2^13), what is the value of x?
A.9
B.11
C.13
D.15
E.17
OA is 15
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If 2^x - 2^x-2=3(2^13), what is the value of x
just understand one simple thing
2^x-2 can be written as 2^x/2^2 = 2^x/4 ( a^m/a^n= a^m-n)
thats it
take 2^x common in the equation
2^x( 1- 1/4) = 3(2^13)
solve this
2^x (3/4) = 3(2^13)
cancel 3 on both sides
2^x = 4( 2^13)
2^x = 2^2* 2^13 ( a^m*a^n = a^m+n)
there fore x =15
i hope it helps ...
just understand one simple thing
2^x-2 can be written as 2^x/2^2 = 2^x/4 ( a^m/a^n= a^m-n)
thats it
take 2^x common in the equation
2^x( 1- 1/4) = 3(2^13)
solve this
2^x (3/4) = 3(2^13)
cancel 3 on both sides
2^x = 4( 2^13)
2^x = 2^2* 2^13 ( a^m*a^n = a^m+n)
there fore x =15
i hope it helps ...