Tính A = 1 - 2019^1 + 2019^2 + 2019^3 +...+ 2019^2018 + 2019^2019

Bài 1.Tìm x:
1.(x+2)+(4x+4)+(7x+6)+...+(25x+18)+(28x+20)=1560
2.(x+1)+(x+2)+(x+3)+...+(x+100)=5750
3.(x-1)+(x-2)+(x-3)+...+(x-100)=100
4.(2x-1)+(4x-2)+..+(400x-200)=5+10+..+1000
Bài 2.Tính
A=1-2019^1+2019^2+2019^3+...+2019^2018+2019^2019