Ôîðìóëû ïðîèçâîäíûõ îñíîâíûõ ýëåìåíòàðíûõ ôóíêöèè.

1.Ñ’ = 0

2.x’=1

3.(u+v)’=u’+v’

4.(uv)’=u’v+uv’

5.(cu)’= cu’

6.(u/v)’= u’v-uv’/v2

7.(un)’= nun-1*u’

8þ(√ã)ý=(1.2√ã)*ãý

9þ(1.ã) =-1.ã2*ãý

10þ(óã)ý= óã*ãý

11.(au)’= au lna*u’

12.(lnu)’=1/u*u’

13.(logau)’ = (1/ulna)*u’

Âûâîäèì ôîðìóëó y=lnx

1.Äàäèì àðãóìåíòó õ ïðèðàùåíèå∆x≠0è íàéäåì íàðàùåííîå çíà÷åíèå ôóíêöèè y+∆y=f(x+∆x)

x. ∆x≠0 y+∆y=ln(x+∆x)

2.Íàõîäèì ïðèðàùåíèå ôóíêöèè∆y=f(x+∆x)-f(x)

∆y=ln(x+∆x)-lnx=ln(x+∆x/x)= ln (1+∆x/x)

3.Cîñòàâëÿåì îòíîøåíèå ∆y/∆x

∆y/∆x= 1/∆x*ln (1+∆x/x)

4.Íàõîäèì ïðåäåë ýòîãî îòíîøåíèÿ ïðè ∆x→0

ò.å. y’=lim∆y/∆x (åñëè ýòîò ïðåäåë ñóùåñòâóåò).

y’= lim∆y/∆x= lim 1/∆xln(1+∆x/x)= (0/0)= lim ln(1+y)/xy=1/xlimln(1+y)1/y= 1/xlimlne=1/x