Log vs ln
Logarithm yog lub tswv yim ua lej muaj txiaj ntsig zoo uas pab daws cov teeb meem lej nyuaj. Logarithms, hais lus yooj yim yog exponents. Lub zog uas lub hauv paus ntawm 10 yuav tsum tau tsa kom tau txais tus lej hu ua nws tus lej log, thiab lub zog uas lub hauv paus e yuav tsum tau tsa kom tau tus lej yog hu ua lub logarithm ntawm tus lej. John Napier, tus kws lej, tau qhia txog lub tswv yim ntawm logarithms nyob rau xyoo pua 17th kom suav tau yooj yim dua. Muaj ntau tus neeg uas nyob twj ywm tsis meej pem ntawm cav thiab ln, thiab tsab xov xwm no sim kom paub qhov txawv ntawm cav thiab ln.
Log rau hauv paus 10 ntawm 100=2, as 10X10=100, uas yog Log 10 100=Log 10 10 2=2
Ntawm no, 10 yog lub hauv paus, 2 yog lub logarithm, thiab 100 yog tus lej uas nws lub log yog 2. logarithms rau lub hauv paus 10 yog hu ua cov logarithms, lossis yooj yim log. Ntawm qhov tod tes, logarithms rau lub hauv paus e (loge) yog hu ua natural logarithms los yog yooj yim ln (pronounced lon).
Raws qhov sib txawv ntawm cov cav thiab ln, thiab lawv cuam tshuam li cas, saib cov kab zauv hauv qab no.
Log x yog tus lej ntawm 10 uas muab rau koj ib tus lej. Peb paub tias 10X10=100, ces log 100=2
Ib yam zoo sib xws, ln x yog tus lej ntawm e thiab tsis yog 10, yog li, muab qhov sib txawv.
Peb paub tias e=2.18281828459, thiab e X e=7.389056
Hence ln 7.389056=2
