(-2)49+(-2)48+(-2)47+.+(-2)+1问题的49.48.47是指49次方,48次方,47次方.计算此题.

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(-2)49+(-2)48+(-2)47+.+(-2)+1问题的49.48.47是指49次方,48次方,47次方.计算此题.

(-2)49+(-2)48+(-2)47+.+(-2)+1问题的49.48.47是指49次方,48次方,47次方.计算此题.
(-2)49+(-2)48+(-2)47+.+(-2)+1
问题的49.48.47是指49次方,48次方,47次方.计算此题.

(-2)49+(-2)48+(-2)47+.+(-2)+1问题的49.48.47是指49次方,48次方,47次方.计算此题.
设s=(-2)^49+(-2)^48+……+(-2)^1+1
则(-2)*s=(-2)^50+(-2)^49+(-2)^48+……+(-2)^1
s-(-2)s=[(-2)^49+(-2)^48+……+(-2)^1+1]-[(-2)^50+(-2)^49+(-2)^48+……+(-2)^1]
中间正负抵消
s+2s=1-(-2)^50
3s=1-2^50
s=(1-2^50)/3

(-2)49+(-2)48+(-2)47+.........+(-2)+1
=[(-2)^49+(-2)^48]+[(-2)^47+(-2)^46]+....+[(-2)^3+(-2)^2]+(-2)+1
=[2^48*(-2+1)]+[2^46*(-2+1)]+....+[2^2*(-2+1)]+(-2+1)
=-2^48-2^46-2^44-....-2^2-1
=-[4*(1-4^24)/(1-4)]-1
=-4^25/3-5/4

y=0
for i=49 to 0 step -1
x=(-2)^i
y=y+x
endfor
?y
得出结果:-375299968947541