Tính bằng cách hợp lí:
a.\(\frac{2011x2010-1}{2009x2011+2010}\)
b. 10,11 + 11,12 + 12,13 + ... + 97,98 + 98.99 + 99.100
Không tính cụ thể , hãy sắp xếp các biểu thức sau theo thứ tự giảm dần :
\(\frac{\frac{2010}{2011}}{\frac{2012}{2013}}+\frac{\frac{2011}{2012}}{\frac{2013}{2014}}+\frac{\frac{2012}{2013}}{\frac{2014}{2015}}\)
\(\frac{\frac{2010}{2011}+\frac{2011}{2012}+\frac{2012}{2013}}{\frac{2012}{2013}+\frac{2013}{2014}+\frac{2014}{2015}}\)
\(\frac{\frac{2010+2011+2012}{2011+2012+2013}}{\frac{2012+2013+2014}{2013+2014+2015}}\)
\(\frac{\frac{2010}{2011}+\frac{2011}{2012}+\frac{2012}{2013}}{\frac{2012+2013+2014}{2013+2014+2015}}\)
\(\frac{\frac{2010+2011+2012}{2011+2012+2013}}{\frac{2012}{2013}+\frac{2013}{2014}+\frac{2014}{2015}}\)
So sánh:\(\frac{2010}{2011}+\frac{2011}{2012}+\frac{2012}{2013}+\frac{2013}{2014}\)và\(\frac{2010}{2008}+\frac{2011}{2013}+\frac{2012}{2014}+\frac{2013}{2015}\)
a = 2010/2011 + 2011/2012 + 2012/2013 so sánh a và b
b = 2010/2011 + 2011/2012 + 2012/2013
2012 x 2010 + 2011 phần 2010 x 2013 + 1
tính nhanh
giúp mik vs
2009x2011-1/2011x2010-2012
2011/2010 *2012/2011 * 2013/2012 * 2014/2013 * 1005/1007
dấu * là dấu nhân
1/3x5 + 1/5x7 + 1/7x9 + ... + 1/2009x2011
4/1x3+4/3x5+4/5x7+...+4/2009x2011