So sánh: A = (10^2018 + 3)/(10^2017 + 3) và B = (10^2017 + 3)/(10^2016 + 3)
Không dùng máy tính hãy so sánh A=10^2016+2018/10^2017+2018 và B=10^2017+2018/10^2018+2018
Ta có: \(A=\frac{10^{2016}+2018}{10^{2017}+2018}\)\(\Rightarrow10A=\frac{10^{2017}+2018.10}{10^{2017}+2018}=\frac{10^{2017}+2018+2018.9}{10^{2017}+2018}=1+\frac{2018.9}{10^{2017}+2018}\)
Tương tự ta có: \(10B=1+\frac{2018.9}{10^{2018}+2018}\)
Vì \(2017< 2018\)\(\Rightarrow10^{2017}< 10^{2018}\)\(\Rightarrow10^{2017}+2018< 10^{2018}+2018\)
\(\Rightarrow\frac{2018.9}{10^{2017}+2018}>\frac{2018.9}{10^{2018}+2018}\)\(\Rightarrow1+\frac{2018.9}{10^{2017}+2018}>1+\frac{2018.9}{10^{2018}+2018}\)
hay \(10A>10B\)\(\Rightarrow A>B\)
Vậy \(A>B\)
Ta có : \(A=\frac{10^{2016}+2018}{10^{2017}+2018}\)
\(\Rightarrow10A=\frac{10^{2017}+20180}{10^{2017}+2018}=\frac{10^{2017}+2018+18162}{10^{2017}+2018}=1+\frac{18162}{10^{2017}+2018}\)
Ta có : \(B=\frac{10^{2017}+2018}{10^{2018}+2018}\)
\(\Rightarrow\frac{10^{2018}+20180}{10^{2018}+2018}=\frac{10^{2018}+2018+18162}{10^{2018}+2018}=1+\frac{18162}{10^{2018}+2018}\)
Vì \(10^{2017}+2018< 10^{2018}+2018\) nên \(\frac{18162}{10^{2017}+2018}>\frac{18162}{10^{2018}+2018}\)
\(\Rightarrow1+\frac{18162}{10^{2017}+2018}>1+\frac{18162}{10^{2017}+2018}\Rightarrow10A>10B\Rightarrow A>B\)
Vậy A > B
Làm khác bạn kia 1 xíu à
Hãy so sánh:
A=10^2016+2018/10^2017+2018
B=10^2017+2018/10^2018+2018
nhanh lên các bn mik cần gấp
So sánh A và B:
A=\(\frac{10^{2016}+2018}{10^{2017}+2018^{ }}\)
B=\(\frac{10^{2017}+2018}{10^{2018}+2018}\)
\(+)A=\frac{10^{2016}+2018}{10^{2017}+2018}\)
\(10A=\frac{10^{2017}+20180}{10^{2017}+2018}=1+\frac{18162}{10^{2017}+2018}\left(1\right)\)
\(+)10B=\frac{10^{2018}+20180}{10^{2018}+2018}=1+\frac{18162}{10^{2018}+2018}\left(2\right)\)
Từ (1),(2)=> \(\frac{18162}{10^{2017}+2018} >\frac{18162}{10^{2018}+2018}\)
=> 10A>10B
=>A>B
So sánh:
a) A = 102016 - 2 / 102017 - 2 và B = 202015 + 1 / 102016 + 1
b) A = 20162017 - 3 / 20162018 - 3 và B = 20162016 + 3 / 20162017 + 3
c) A = 20172016 - 2015 / 20172017 - 2015 và B = 20172015 + 1 / 20172016 + 1
so sánh A = 10 mũ 2017 + 1 / 10 mũ 2018 + 1 và B = 10 mũ 2016 +1 /10 mũ 2017
so sánh a và b biết a=2016/2017+2017/2018+2018/2019+2019/2016 và b=1/8+1/9+1/10+...+1/63
Cho A= 102016+1/102017+1;B=102017+1/102018+1
So sánh A và B
Ta có : \(10.A=\frac{10^{2017}+10}{10^{2017}+1}=\frac{10^{2017}+1+9}{10^{2017}+1}=\frac{10^{2017}+1}{10^{2017}+1}+\frac{9}{10^{2017}+1}=1+\frac{9}{10^{2017}+1}\)
\(10.B=\frac{10^{2018}+10}{10^{2018}+1}=\frac{10^{2018}+1+9}{10^{2018}+1}=\frac{10^{2018}+1}{10^{2018}+1}+\frac{9}{10^{2018}+1}=1+\frac{9}{10^{2018}+1}\)
Vì \(1=1\)và \(\frac{9}{10^{2017}+1}>\frac{9}{10^{2018}+1}\)nên \(1+\frac{9}{10^{2017}+1}>1+\frac{9}{10^{2018}+1}\)hay \(A>B\)
Vậy \(A>B\)
so sánh 2 phân số sau:\(A=\frac{10^{2016}+10}{10^{2017}+10};B=\frac{10^{2017}-10}{10^{2018}-10}\)
dễ mà bạn
A=10x10+10/ 10x10x10+10
A=110/1010
a=11/101
b=10x10-10/10x10x10-10
b=90/990
b=11/110
vậy a=11/101
b=90/990
bn tự so sánh nhé ^-^
mik mỏi tay quá ko đánh đc nữa bọn mik bằng tuổi đó
câu này mik học trên lớp rùi
so sánh A và B
A = 102016+1 /102017+1
B = 102017+1 / 102018+1
\(A=\frac{10^{2016}+1}{10^{2017}+1}\)
\(A=\frac{10^{2016}+1}{10^{2017}+1}+\frac{10^{2017}+1}{10^{2017}+1}\)
\(A=\frac{10^{2016}+1+10^{2017}+1}{10^{2017}+1}\)
\(A=\frac{10^{2016}+10^{2017}+1+1}{10^{2016}.10+1}\)
\(A=\frac{10^{2016}.\left(1+10\right)+2}{10^{2016}.10+1}\)
\(A=\frac{10^{2016}.11+2}{10^{2016}.10+1}\)
\(A=\frac{11+2}{10+1}\)
\(A=\frac{13}{11}\)(1)
Làm tương tự phần B
Từ 1 và 2
\(\Leftrightarrow\)\(\frac{13}{11}=\frac{13}{11}\)
\(\Leftrightarrow\)A = B