So sánh: x=2015.2016+2/2015.2016 va y=2016.2017+2/2016.2017
Giúp mik nha cần gấp
a) Hãy so sánh M=2015.2016-1/2015.2016 với N=2016.2017-1/2016.2017
Cho A=2015.2016/2015.2016+1 và B=2016.2017/2016.2017+1
So sánh A vs B
Bạn nào giải đc mk sẽ tick
So sánh :
2015.2016-1
2015.2016
và
2016.2017-1
2016.2017
1. So sanh :
a) \(\frac{2015.2016-1}{2016.2015}\) va \(\frac{2016.2017-1}{2016.2017}\)
b) \(\frac{2015.2016}{2015.2016+1}\) va \(\frac{2016.2017}{2016.2017+1}\)
c) \(\frac{33.10^3}{2^3.5.10^3+7000}\) va \(\frac{3774}{5271}\)
a.\(\frac{2015.2016-1}{2015.2016}=1-\frac{1}{2015.2016}\)
\(\frac{2016.2017-1}{2016.2017}=1-\frac{1}{2016.2017}\)
vì \(\frac{1}{2015.2016}>\frac{1}{2016.2017}\)
=>\(-\frac{1}{2015.2016}< -\frac{1}{2016.2017}\)
=>\(1-\frac{1}{2015.2016}< 1-\frac{1}{2016.2017}\)
so sánh:
a) A=\(\frac{2014.2015-1}{2014.2015}\)và C=\(\frac{2015.2016-1}{2015.2016}\)
b)B=\(\frac{2015.2016+1}{2015.2016}\)và D=\(\frac{2016.2017+1}{2016.2017}\)
1.2+2.3+3.4+....+2015.2016+2016.2017
11.2+12.3+13.4+14.5+...+12015.2016+12016.2017
=1−12+12−13+13−14+14−15+...+12015−12016+12016−12017
=1−12017=20162017
CM:A=1/1.3+1/3.5+1/5.7+...+1/2015.2016<1/2
giup mik nk cần gấp lắm tick choa
\(A=\dfrac{1}{1.3}+\dfrac{1}{3.5}+\dfrac{1}{5.7}+...+\dfrac{1}{2015.2016}=\dfrac{1}{2}\left(1-\dfrac{1}{3}+\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{5}-\dfrac{1}{7}+...+\dfrac{1}{2015}-\dfrac{1}{2016}\right)=\dfrac{1}{2}\left(1-\dfrac{1}{2016}\right)=\dfrac{1}{2}-\dfrac{1}{2016.2}< \dfrac{1}{2}\left(đpcm\right)\)
\(A=\dfrac{1}{1.3}+\dfrac{1}{3.5}+...+\dfrac{1}{2015.2017}\\ =\dfrac{1}{2}\left(\dfrac{2}{1.3}+\dfrac{2}{3.5}+\dfrac{2}{5.7}+...+\dfrac{2}{2015.2017}\right)\\ =\dfrac{1}{2}\left(1-\dfrac{1}{3}+\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{5}-\dfrac{1}{7}+...+\dfrac{1}{2015}-\dfrac{1}{2017}\right)\\ =\dfrac{1}{2}\left(1-\dfrac{1}{2017}\right)\\ < \dfrac{1}{2}.1=\dfrac{1}{2}\)
so sanh
A=2015.2016 va B=2016^2
Sửa đề: A=2015.2017 và B=20162
Ta có: \(A=2015.2017=\left(2016-1\right)\left(2016+1\right)=2016^2-1\)
\(B=2016^2\)
\(\Rightarrow A< B\).
P/s:/=phần(phân số)
Bài 1:so sánh các phân số:
a,A=2015/2016 và B=2026/2017
b,C=1/(31)+1/(32)+1/(33)+...+1/(89)+
1/(90) và D=5/6
c,E=(2015.2016-1)/(2015.2016) và
F=(2016.2017-1)/(2016/2017)
d,G=(10^11)-1/(10^12)-1 và
H=(10^10)+1/(10^11)+1