SOLUTION: my question is: Why is the following incorrect? AND I have to provide an example proving the answer log2(x + y) = log2x + log2y

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Question 508329: my question is:
Why is the following incorrect? AND I have to provide an example proving the answer
log2(x + y) = log2x + log2y
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Simple example:

log2(1 + 0) = log2(1) + log2(0)

log2(1) = log2(1) + log2(0)

0 = 0 + Undefined ... since the log of 0 isn't defined

So we then get 0 = undefined, which doesn't make any sense because 0 is defined.

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Another example:


log2(4+4) = log2(4) + log2(4)

log2(8) = log2(4) + log2(4)

3 = 2 + 2

3 = 4 ... which is clearly false


Either example shows that