函數(shù)f（x）=Asin（2x+φ）,當(dāng)x=-π/3時(shí),最小值為-4,
最小值為-4,A=4
f（x）=4sin（2x+φ）,經(jīng)過點(diǎn)（-π/3,-4）
4sin（-2π/3+φ）=-4
sin（-2π/3+φ）=-1
-2π/3+φ=-π/2
φ=π/6
f（x）=4sin（2x+π/6）a2=2a4=42d=a4-a2=2d=1a1=1an=nSn=n(n+1)/21/Sn=2/n(n+1)=2[1/n-1/(n+1)]Tn=2[1-1/2+1/2-1/3+ ????+1/n-1/(n+1)]=2[1-1/(n+1)]=2n/(n+1)???????f??x??=lnx??g??x??=k??x??1??/x????k=e???????h??x??=f??x??-g??x??????????????????????f??x????g??x??????????k??1??h(x)=lnx-e+e/x ??????x>0h'(x)=1/x-e/x^2h'(x)=0 x=e?????e??+?????????0??e????С?h(e)=2-e??2????y=lnx-k+k/xy'=1/x-k/x^2=(x-k)/x^2x=k y????С?ymin=lnk-k+1lnk-k+1>=0