Question

0.1x+0.2=0.5

Answer 1

您好，解方程0.1x+0.2=0.5
可得：0.1x=0.5-0.2
则：x=0.3/0.1=3

Answer 2

c'=0(c为常数） (x^a)'=ax^(a-1),a为常数且a≠0 (a^x)'=a^xlna (e^x)'=e^x (logax)'=1/(xlna),a>0且 a≠1 (lnx)'=1/x (sinx)'=cosx (cosx)'=-sinx (tanx)'=(secx)^2 (secx)'=secxtanx (cotx)'=-(cscx)^2 (cscx)'=-csxcotx (arcsinx)'=1/√(1-x^2) (arccosx)'=-1/√(1-x^2) (arctanx)'=1/(1+x^2) (arccotx)'=-1/(1+x^2) (shx)'=chx (chx)'=shx d(Cu)=Cdud(u+-v)=du+-dvd(uv)=vdu+udvd(u/v)=(vdu-udv)/