SOLUTION: If n is a positive integer and {{{(n+1)/2^n = 1/2}}}, then n= a.1 b.2 c.3 d.4 e.5

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Question 549835: If n is a positive integer and %28n%2B1%29%2F2%5En+=+1%2F2, then n=
a.1
b.2
c.3
d.4
e.5
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
%28n%2B1%29%2F2%5En+=+1%2F2
Try out the possible answers and see which one(s) works:

Try a. 1

%28n%2B1%29%2F2%5En+=+1%2F2
%281%2B1%29%2F2%5E1+=+1%2F2
2%2F2+=+1%2F2
1+=+1%2F2

No, that's false.


Try b. 2

%28n%2B1%29%2F2%5En+=+1%2F2
%282%2B1%29%2F2%5E2+=+1%2F2
3%2F4+=+1%2F2

No, that's false.

Try c. 3

%28n%2B1%29%2F2%5En+=+1%2F2
%283%2B1%29%2F2%5E3+=+1%2F2
4%2F8+=+1%2F2
1%2F2+=+1%2F2

Yes, that's true.

Try d. 4

%28n%2B1%29%2F2%5En+=+1%2F2
%284%2B1%29%2F2%5E4+=+1%2F2
5%2F16+=+1%2F2

No, that's false.

Try e. 5

%28n%2B1%29%2F2%5En+=+1%2F2
%285%2B1%29%2F2%5E5+=+1%2F2
6%2F32+=+1%2F2
3%2F16+=+1%2F2

No, that's false.

Looks like c. 3 is the only one that works.

This demonstrates a trick for you to use when you are
taking a multiple choice test.  If you run into a 
problem that you don't know how to solve directly, 
try out all the possible choices.

Edwin