262logarithm is not defined for non positive numbers.
Anurag Choudhury why not?Upvote·0· Reply ·2012-07-19 02:46:02
Why is the value of log-3-27 ≠3?
Because... log-3-27 = log-3(-3 * 9)=log-3-3 + log-39 = 1 + 2 = 3
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7 Answers
1357@Anurag
logax=N
then we have aN=x
which we define only when a is positive and not equal to 1.
(a)N will remain positive for all value of N.
so x will remain positive.
and so x is greater than 0
262
45LOG IS NOT DEFINED FOR NEGATIVE BASES
- Anurag Choudhury why the hell not???????
11why we cant define aN=x,when a is +ve?
-3*-3*-3=-27
(-3)3=-27.
- Manish Shankar because then it will not be true for all values of N.
e.g.
what is (-3)[p]-1/2[\p]
1SEE...
log-3(-27) can be written as loge(-27)/loge(-3)...now
lets take loge(-27)=y
then ey=-27,now we all know that e is a positive quantity(with value 2.71828)now its power can never yield a negative result therefore loga(variable) is only defined for var>0 && a>0...
11If the base of a log is -ve it's value cannot be determined !!!!
21Sir, we can have values like
\log z=\log|z|+i\arg(z)
So, why cannot we have values for negative reals?
The answer might not be in reals but we can have.