giải các bất phương trình sau
a,(x-5/2005)+(x-15/1995)<(x-2005/5)+(x-1995/15)
b,(1987-x/15)+(1988-x/16)+(27+x/1999)+(28+x/2000)>4
c,(1/1.101+1/2.102+...+1/10.110)x >=1/1.11+1/1.12+..+1/100.110
Giải các bất phương trình sau:
a) \(\frac{x-5}{2005}+\frac{x-15}{1995}< \frac{x-2005}{5}+\frac{x-1995}{15}\)
b)\(\frac{1987-x}{15}+\frac{1988-x}{16}+\frac{27+x}{1999}+\frac{28+x}{2000}>4\)
x-5/1995+x-15/1985+x-25/1985=x-1995/5+x-1985/15+x-1925/75
CMĐT: 1996 x 1989 -1993 x 1998 x 1995 = 2005 x 2010 x 2003 - 2007 x 2002 x2009.
a,x-10/1994+x-8/1996+x-6/1998+x-4/2000+x-2/2002=x-2002/2+x-2000/4+x-1998/6+x-1996/8+x-1994/10
b,x-1991/9+x-1993/7+x-1995/5+x-1997/3+x-1999/1=x-9/1991+x-7/1993+x-5/1995+x-3/1997+x-1/1999
c,x-1/13-2x-13/15=3x-15/27-4x-27/29
\(\frac{x-1991}{9}+\frac{x-1993}{7}+\frac{x-1995}{5}+\frac{x-1997}{3}+\frac{x-1999}{1}=\frac{x-9}{1991}+\frac{x-7}{1993}+\frac{x-5}{1995}+\frac{x-3}{1997}+\frac{x-1}{1999}\)
tìm x biết 7-x/1993+5-x/1995+3-x/1997
Tìm phần dư của phép chia
\(x^{19}+x^5-x^{1995}:\left(x^2-1\right)\)
Vì x=7 \(\Rightarrow8=x+1\)thay vào B ta được :
\(B=x^{2006}-\left(x+1\right)x^{2005}+\left(x+1\right)x^{2004}-....-\left(x+1\right)x-5\)
\(=x^{2006}-x^{2006}-x^{2005}+x^{2005}+x^{2004}-...-x^2-x-5\)
\(=-x-5\)Thay x=7 vào B ta được :
\(B=-7-5\)
\(=-12\)
Vậy \(B=-12\)tại x=7
