A = 1 + 2016 + 2016^2 + … + 2016^2016;
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Ta có:A=\(\frac{2016^{2016}+2}{2016^{2016}-1}\)>1
=>A<\(\frac{2016^{2016}+2-2}{2016^{2016}-1-2}\)=\(\frac{2016^{2016}}{2016^{2016}-3}\)=B
=>A<B(công thức nếu \(\frac{a}{b}\)>1 thì \(\frac{a}{b}\)<\(\frac{a-n}{b-n}\)(nEN)
CM công thức:
Ta có \(\frac{a}{b}\)>1=>a>b=>a=b+n(nEN)
Ta so sánh \(\frac{a}{b}\) và \(\frac{a-n}{b-n}\)(nEN)
Mà a*(b-n)=ab-an=ab-(b+n)*n=ab-(bn+n2)=ab-bn-n2
b*(a-n)=ba-bn
Vì ab-bn-n2<ba-bn
=>\(\frac{a}{b}\)<\(\frac{a-n}{b-n}\)
a, - { -(2016 +2015) - [ - (2016 - 2015) - (2016+2015) ] }
= -{-(2016+2015)-[-0-0]}
= -{-4031-0-0}
=-4031
\(A=\frac{2016^{2016}+2}{2016^{2016}-1}=\frac{2016^{2016}-1+3}{2016^{2016}-1}=\frac{2016^{2016}-1}{2016^{2016}-1}+\frac{3}{2016^{2016}-1}=1+\frac{3}{2016^{2016}-1}\)
\(B=\frac{2016^{2016}}{2016^{2016}-3}=\frac{2016^{2016}-3+3}{2016^{2016}-3}=\frac{2016^{2016}-3}{2016^{2016}-3}+\frac{3}{2016^{2016}-3}=1+\frac{3}{2016^{2016}-3}\)
ta thấy:20162016-1>20162016-3
=>\(\frac{3}{2016^{2016}-1}<\frac{3}{2016^{2016}-3}\)
=>\(1+\frac{3}{2016^{2016}-1}<1+\frac{3}{2016^{2016}-3}\)
=>A<B
A = 20162016 + 2/20162016-1 = 20162016 - 1 + 3/20162016 - 1
= 20162016 - 1/20162016 - 1 + 3/20162016 - 1
= 1 + 3/20162016 - 1 (không biết ghi hỗn số)
B = 20162016/20162016 -3 = 20162016 - 3 + 3/20162016 - 3
= 20162016 - 3/20162016 - 3 + 3/20162016 - 3
= 1 + 3/20162016 - 3
So sánh : 1 + 3/20162016 - 1 và 1 + 3/20162016 - 3
Ta có : 1 + 3/20162016 - 1 < 1 + 3/20162016 - 3
=> A < B
Ta có :
\(A=\frac{2016^{2016}+2}{2016^{2016}-1}=\frac{2016^{2016}-1+3}{2016^{2016}-1}=1+\frac{3}{2016^{2016}-1}\)
\(B=\frac{2016^{2016}}{2016^{2016}-3}=\frac{2016^{2016}-3+3}{2016^{2016}-3}=1+\frac{3}{2016^{2016}-3}\)
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 !!!
\(A=\frac{1}{2016}+\frac{2}{2016}+\frac{3}{2016}+...+\frac{2015}{2016}\)
\(A=\frac{1+2+3+...+2015}{2016}=\frac{2031120}{2016}=\frac{2015}{2}\)
Ta có :A=\(\frac{1}{2016}+\frac{2}{2016}+...+\frac{2015}{2016}=\frac{1+2+...+2015}{2016}\)
Xét 1+2+ ... +2015 = \(\frac{2015\times2016}{2}=2031120\)---> A=\(\frac{2031120}{2016}=1007,5\)
=(1+2+3+...+2015)/2016=(2015.(2015+1):2)/2016=2031120/2016=2015/2
Ta có:
\(A=1+2016+2016^2+...+2016^{2016}\)
\(\Rightarrow2016A=2016.\left(1+2016+2016^2+...+2016^{2016}\right)\)
\(=2016+2016^2+2016^3...+2016^{2017}\)
\(\Rightarrow2016A-A=\left(2016+2016^2+2016^3...+2016^{2017}\right)-\left(1+2016+2016^2+...+2016^{2016}\right)\)
\(\Rightarrow2015A=2016^{2017}-1\)
\(\Rightarrow A=\frac{2016^{2017}-1}{2015}\)
Vậy \(A=\frac{2016^{2017}-1}{2015}\)