K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

16 tháng 8 2016

\(\frac{2015\cdot2016+1561}{2015\cdot2017-454}\)

\(=\frac{2015\cdot2016+1561}{2015\cdot\left(2016+1\right)-454}\)

\(=\frac{2015\cdot2016+1561}{2015\cdot2016+2015\cdot1-454}\)

\(=\frac{2015\cdot2016+1561}{2015\cdot2016+2015-454}\)

\(=\frac{2015\cdot2016+1561}{2015\cdot2016+1561}=1\)

28 tháng 3 2017

Bằng \(-\frac{2}{11}\)

15 tháng 6 2021

Ta có : \(A=\left(\left(-2015\right)^{2016}.-2016^{2017}+\left(-2016\right)^{2017}.-2015^{2016}\right).\left(-2017\right)^{2018}\)

\(=\left(2015^{2016}.-2016^{2017}-2016^{2017}.-2015^{2016}\right).2017^{2018}\)

\(=\left(2015^{2016}-2015^{2016}\right).2017^{2018}.\left(-2016^{2017}\right)\)

\(=0.2017^{2018}.\left(-2016^{2017}\right)=0\)

Giải:

\(A=\left[\left(-2015\right)^{2016}.\left(-2016^{2017}\right)+\left(-2016\right)^{2017}.\left(-2015^{2016}\right)\right].\left(-2017\right)^{2018}\) 

\(A=\left[2015^{2016}.\left(-2016\right)^{2017}+\left(-2016\right)^{2017}.\left(-2015^{2016}\right)\right].\left(-2017\right)^{2018}\) 

\(A=\left[2015^{2016}+\left(-2015^{2016}\right)\right].\left(-2016\right)^{2017}.\left(-2017\right)^{2018}\) 

\(A=0.\left(-2016\right)^{2017}.\left(-2017\right)^{2018}\) 

\(A=0\)

17 tháng 3 2018

Ta có:\(Q=\frac{2015+2016+2017}{2016+2017+2018}=\frac{2015}{2016+2017+2018}+\frac{2016}{2016+2017+2018}+\frac{2017}{2016+2017+2018}\)

Vì \(\hept{\begin{cases}\frac{2015}{2016}>\frac{2015}{2016+2017+2018}\\\frac{2016}{2017}>\frac{2016}{2016+2017+2018}\\\frac{2017}{2018}>\frac{2017}{2016+2017+2018}\end{cases}}\)

\(\Rightarrow\frac{2015}{2016}+\frac{2016}{2017}+\frac{2017}{2018}>\frac{2015}{2016+2017+2018}+\frac{2016}{2016+2017+2018}+\frac{2017}{2016+2017+2018}\)

\(\Rightarrow P>Q\)

Vậy P > Q