Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Ta có :
\(A=\frac{2016^{2016}+2}{2016^{2016}-1}=\frac{\left(2016^{2016}-1\right)+3}{2016^{2016}-1}=1+\frac{3}{2016^{2016}-1}\)
\(B=\frac{2016^{2016}}{2016^{2016}-3}=\frac{\left(2016^{2016}-3\right)+3}{2016^{2016}-3}=1+\frac{3}{2016^{2016}-3}\)
Vì \(2016^{2016}-1>2016^{2016}-3\) nên \(\frac{3}{2016^{2016}-1}< \frac{3}{2016^{2016}-3}\)
\(\Rightarrow1+\frac{3}{2016^{2016}-1}< 1+\frac{3}{2016^{2016}-3}\)
\(\Rightarrow A< B\)
\(A=\frac{2016^{2016}-1+3}{2016^{2016}-1};B=\frac{2016^{2016}-3+3}{2016^{2016}-3}\)
\(A=\frac{2016^{2016}-1}{2016^{2016}-1}+\frac{3}{2016^{2016}-1};B=\frac{2016^{2016}-3}{2016^{2016}-3}+\frac{3}{2016^{2016}-3}\)
\(A=1+\frac{3}{2016^{2016}-1};B=1+\frac{3}{2016^{2016}-3}\)
Vì \(\frac{3}{2016^{2016}-1}< \frac{3}{2016^{2016}-3}\)
\(\Rightarrow1+\frac{3}{2016^{2016}-1}< 1+\frac{3}{2016^{2016}-3}\)
\(\Rightarrow A< B\)
\(A=\frac{2016^{2016}+2}{2016^{2016}-1}=\frac{2016^{2016}-1+3}{2016^{2016}-1}=1+\frac{3}{2016^{2016}-1}\)
\(B=\frac{2016^{2016}}{2016^{2016}-3}=\frac{2016^{2016}-3+3}{2016^{2016}-3}=1+\frac{3}{2016^{2016}-3}\)
Do \(\frac{3}{2016^{2016}-1}>\frac{3}{2016^{2016}-3}\)
\(\Rightarrow1+\frac{3}{2016^{2016}-1}>1+\frac{3}{2016^{2016}-3}\)
\(\Rightarrow A>B\)
Vậy \(A>B\)
Chúc bạn học tốt !!!
Vì \(2016^{2016}+1< 2016^{2017}+1\) nên \(\frac{2016^{2016}+1}{2016^{2017}+1}< 1\)
\(\Rightarrow A=\frac{2016^{2016}+1}{2016^{2017}+1}< \frac{2016^{2016}+1+2015}{2016^{2017}+1+2015}=\frac{2016^{2016}+2016}{2016^{2017}+2016}=\frac{2016\left(2016^{2015}+1\right)}{2016\left(2016^{2016}+1\right)}=\frac{2016^{2015}+1}{2016^{2016}+1}=B\)Vậy A < B
P \(=\left(1-\frac{1}{2^2}\right).\left(1-\frac{1}{3^2}\right).\left(1-\frac{1}{4^2}\right)...\left(1-\frac{1}{50^2}\right)\)
P\(=\frac{2^2-1}{2^2}.\frac{3^2-1}{3^2}.\frac{4^2-1}{4^2}...\frac{50^2-1}{50^2}\)
P \(=\frac{1.3}{2.2}.\frac{2.4}{3.3}.\frac{3.5}{4.4}...\frac{49.51}{50.50}\)
P\(=\frac{\left(1.2.3...49\right).\left(3.4.5...51\right)}{\left(2.3.4...50\right).\left(2.3.4...50\right)}\)
P\(=\frac{1.51}{50.2}=\frac{51}{100}\)
Ta có
\(2016A=\frac{2016^{2017}+2016}{2016^{2017}+1}=\frac{2016^{2017}+1}{2016^{2017}+1}+\frac{2015}{2016^{2017}+1}=1+\frac{2015}{2016^{2017}+1}\)
\(2016B=\frac{2016^{2016}+2016}{2016^{2016}+1}=\frac{2016^{2016}+1}{2016^{2016}+1}+\frac{2015}{2016^{2016}+1}=1+\frac{2015}{2016^{2016}+1}\)
Do \(\frac{2015}{2016^{2017}+1}< \frac{2015}{2016^{2016}+1}\Rightarrow2016A< 2016B\Rightarrow A< B.\)
B = \(\frac{2016^{2015}+1}{2016^{2016}+1}\)< A =\(\frac{2016^{2016}+1}{2016^{2017}+1}\)
Đặt C = 1 + 2017 + 20172 + ... + 20172016 ; D = 1 + 2016 + 20162 + ... + 20162016
Ta có : 2017C = 2017 + 20172 + 20173 + ... + 20172017
=> 2016C = 2017C - C = 20172017 - 1\(\Rightarrow C=\frac{2017^{2017}-1}{2016}\)
2016D = 2016 + 20162 + 20163 + ... + 20162017
=> 2015D = 2016D - D = 20162017 - 1\(\Rightarrow D=\frac{2016^{2017}-1}{2015}\)
\(\Rightarrow A=\frac{2017^{2017}}{\frac{2017^{2017}-1}{2016}}=\frac{2017^{2017}.2016}{2017^{2017}-1}\);\(B=\frac{2016^{2017}}{\frac{2016^{2017}-1}{2015}}=\frac{2016^{2017}.2015}{2016^{2017}-1}\)
Ta có : 20172017.2016.(20162017 - 1) - 20162017.2015.(20172017 - 1)
= 20172017.20162017.2016 - 20172017.2016 - 20172017.20162017.2015 + 20162017.2015
= 20172017.20162017 - 20172017.2016 + 20162017.2015
= 20172017.(20162017 - 2016) + 20162017.2015 > 0
=> A > B
Ta có
\(A=1:\frac{1+2017+2017^2+...+2017^{2016}}{2017^{2017}}\)
\(B=1:\frac{1+2016+2016^2+...2016^{2016}}{2016^{2017}}\)
\(A=1:\left(\frac{1}{2017^{2017}}+\frac{1}{2017^{2016}}+\frac{1}{2017^{2015}}+...+\frac{1}{2017}\right)\)
\(B=1:\left(\frac{1}{2016^{2017}}+\frac{1}{2016^{2016}}+\frac{1}{2016^{2015}}+...+\frac{1}{2016}\right)\)
Có 20172017>20162017 ; 20172016>20162016 ; 20172015>20162015;..... ; 2017>2016
=> \(\frac{1}{2017^{2017}}< \frac{1}{2016^{2017}};\frac{1}{2017^{2016}}< \frac{1}{2016^{2016}};\frac{1}{2017^{2015}}< \frac{1}{2016^{2015}};...;\frac{1}{2017}< \frac{1}{2016}\)
=> \(\frac{1}{2017^{2017}}+\frac{1}{2017^{2016}}+\frac{1}{2017^{2015}}+...+\frac{1}{2017}< \frac{1}{2016^{2017}}+\frac{1}{2016^{2016}}+\frac{1}{2016^{2015}}+...+\frac{1}{2016}\)
=> A>B ( vì số bị chia và số chia của A và B đều dương, số bị chia của cả 2 đều là 1, cái nào có số chia nhỏ hơn thì lớn hơn)
Easy.
Ta có: Nếu \(\frac{a}{b}>1\)thì \(\frac{a}{b}>\frac{a+m}{b+m}\left(m>0\right)\) (bạn tự c/m)
Mặt khác,ta có: \(C=\frac{2016^{99}+1}{2016^{89}+1}=\frac{2016\left(2016^{99}+1\right)}{2016\left(2016^{89}+1\right)}\)
\(=\frac{2016^{100}+2016}{2016^{90}+2016}=\frac{\left(2016^{100}+1\right)+2015}{\left(2016^{90}+1\right)+2015}\)
Mà \(\frac{\left(2016^{100}+1\right)+2015}{\left(2016^{90}+1\right)+2015}>1\)
Nên \(C=\frac{\left(2016^{100}+1\right)+2015}{\left(2016^{90}+1\right)+2015}< \frac{2016^{100}+1}{2016^{90}+1}=B\)
Vậy \(B>C\)
bằng nhau