if we know log(a) and log(b) how we can find log(a+b) approximately to real value?
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if we know log(a) and log(b) how we can find log(a+b) approximately to real value?
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log(exp(log(a))+exp(log(b)))
If a and b are close numbers, you can approximate using the following formula:
.
For example, if a = b, then
why and need to be close for this formula to work?
isn't (in addition to , ofcourse) sufficient?
This formula works OK, but if is some small number, you can remember its logarithm and thus approximate without calculator or paper — that was the point.
ah i see what u mean. thanks! :)