Question

（-2）50次方+（-2）49次方+（-2）48次方+。。。+（-2）+1的值

谢谢。

Answer 1

(-2)^50+(-2)^49+(-2)^48+…+(-2)+1
=2^50-2^49+2^48-2^47+...-2+1,
=2*2^49-2^49+2*2^47-2^47+...-1
=2^49+2^47+...+2+1
设b=2^49+2^47+...+2+1,
所以4b=2^51+2^49+...+2^3+4,
所以4b-b=2^51+1,
所以3b=2^51+1,
所以b=(2^51+1)/3,
即(-2)^50+(-2)^49+(-2)^48+…+(-2)+1=(2^51+1)/3.

Answer 2

(-2)^50+(-2)^49+(-2)^48+…+(-2)+1
=2^50-2^49+2^48-2^47+...-2+1,
=2*2^49-2^49+2*2^47-2^47+...-1
=2^49+2^47+...+2+1
设b=2^49+2^47+...+2+1,
所以4b=2^51+2^49+...+2^3+4,
所以4b-b=2^51+1,
所以3b=2^51+1,
所以b=(2^51+1)/3,
即(-2)^50+(-2)^49+(-2)^48+…+(-2)+1=(2^51+1)/3

Answer 3

(-2)^50+(-2)^49+(-2)^48+…+(-2)+1
=2^50-2^49+2^48-2^47+...-2+1,
=2^49+2^47+...+2+1
设a=2^49+2^47+...+2+1,
所以4a=2^51+2^49+...+2^3+4,
所以4a-a=2^51+1,
所以3a=2^51+1,
所以a=(2^51+1)/3,
即(-2)^50+(-2)^49+(-2)^48+…+(-2)+1=(2^51+1)/3.

Answer 4

应该是(2^51-1)/3

Answer 5

1/3（2^51+1）