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Questions on Logs

The question is
Lnx/x^2 = 0

I need to solve it but for some reason the answer is 1, but I dont get how its one, because if i take the x to the power of 2 to the other side, and E both sides you get

X = e to the power of x^2
Reply 1
Avatar for B_9710
B_9710
18
ln⁡(1)=0 \ln(1)=0 , so we are looking for x/x2 x/x^2 to = 1.
Original post by SunDun111
The question is
Lnx/x^2 = 0

I need to solve it but for some reason the answer is 1, but I dont get how its one, because if i take the x to the power of 2 to the other side, and E both sides you get

X = e to the power of x^2


If you take the x2x^2 to the other side, do you not get 0∗x2=00*x^2=0?
Reply 3
Avatar for SunDun111
SunDun111
OP
11
Original post by rayquaza17
If you take the x2x^2 to the other side, do you not get 0∗x2=00*x^2=0?


Oh yeah, that works out thanks
Reply 4
Avatar for math42
math42
20
Original post by SunDun111
The question is
Lnx/x^2 = 0

I need to solve it but for some reason the answer is 1, but I dont get how its one, because if i take the x to the power of 2 to the other side, and E both sides you get

X = e to the power of x^2


if a/b = 0 then a = 0
I think some of the above didn't realise you meant:

(ln x) / (x2) = 0
Reply 6
Avatar for SunDun111
SunDun111
OP
11
Original post by NadeemKha_Arab
I think some of the above didn't realise you meant:

(ln x) / (x2) = 0


Yeah i did but isnt what they said still true?
Original post by SunDun111
Yeah i did but isnt what they said still true?


Original post by rayquaza17
If you take the x2x^2 to the other side, do you not get 0∗x2=00*x^2=0?


This one is correct^ yes. Did you manage to see how the answer was reached after following this?
Reply 8
Avatar for SunDun111
SunDun111
OP
11
Original post by NadeemKha_Arab
This one is correct^ yes. Did you manage to see how the answer was reached after following this?


yeah taking E to both sides got me X = 1, is the rule a/b=0 means a=0 valid for everything
Original post by SunDun111
yeah taking E to both sides got me X = 1, is the rule a/b=0 means a=0 valid for everything

assuming b is non-zero, yes.
Original post by SunDun111
yeah taking E to both sides got me X = 1, is the rule a/b=0 means a=0 valid for everything


Yep what you'll see with a slightly more complex equations is you can use that rule to help:

e.g. (x2+3) / (3-y3) = 0

This means you can just get rid of the bottom and solve for x. I know this different to your question, but that's basically to show that it works.

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