( 2019 . x - 2019 ) . (2019 . 2018 -2017 )
tìm x
a.1/3 x 2019/2020
b. 2017 x 2018/2019 x 2019/2018
x2019-2019.x2018+2019.x2018+2019.x2017-2019.x2016+......2019.x-200
Giúp mik vs nhé
x2019-2019.x2018+2019.x2018+2019.x2017-2019.x2016+......2019.x-200 Tại x=2018
Giúp mik vs nhé
Sai đề nên t sửa luôn nhé!
Vì \(x=2018\Rightarrow2019=2018+1=x+1\)
\(A=x^{2017}-2019\cdot x^{2018}+2019\cdot x^{2017}-2019\cdot x^{2016}+....+2019\cdot x-200\)
\(\Rightarrow A=x^{2019}-\left(x+1\right)x^{2018}+\left(x+1\right)x^{2017}-\left(x+1\right)x^{2016}+....-\left(x+1\right)x^2+\left(x+1\right)x-200\)
\(\Rightarrow A=x^{2019}-x^{2019}-x^{2018}+x^{2018}+x^{2017}-x^{2017}-x^{2016}+....-x^3-x^2+x^2+x-200\)
\(\Rightarrow A=x-200=2018-200=1818\)
B=x^2020 -2019 x^2019 - x^2018 - 2019 x^2017 - ...-2019x-2020 với x=2020
\(2018^{2019}+2019\times-2018^{2018}+2019\times-2018^{2017}+...+2019\times-2018+2019\)Tìm kết quả
1. Tìm các số nguyên x , y thỏa mãn :
2017 + x2018 + 20172018 = y2018 + y2019 + 20182019
1. Tìm các số nguyên x , y thỏa mãn :
2017 + x2018 + 20172018 = y2018 + y2019 + 20182019
Tính gái trị biểu thức sau tại x = 2018
B = x2019 - 2019 x2018 + 2019 x2017 - … + 2019 x - 1
B=\(x^{2019}-2019.x^{2018}+2019.x^{2017}-...+2019x-1\)
Ta có : 2019 = 1+2018=1+x ( vì x = 2018 )
Suy ra : \(x^{2019}-\left(x+1\right).x^{2018}+\left(x+1\right).x^{2017}-....+\left(x+1\right).x-1\)
=\(x^{2019}-\left(x^{2019}+x^{2018}\right)+\left(x^{2018}+x^{2017}\right)-...+\left(x^2+x\right)-1\)
= \(x^{2019}-x^{2019}-x^{2018}+x^{2018}+x^{2017}-....+x^2+x-1\)
= \(x-1\) mà x =2018
=> \(x-1=2018-1=2017\)
Vậy giá trị của biểu thức B = 2017
cho p(x)=x^2020-2019x^2019+x^2018-2019x^2017+...+x^2019 tinh P(2019)
Cho x,y là số thục biết x^2016 +y^2016= x^2017 + y^2017= x^2018 +y^2018. Tính x^2019 + y^2019