18.计算:1+1/2+1/(2^2)+1/(2^3)+1/(2
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1+1/2+1/2^2+1/2^3+1/2^4+……+1/2^97-1/2^99
咨询记录 · 回答于2022-11-14
18.计算:1+1/2+1/(2^2)+1/(2^3)+1/(2
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1+1/2+1/2^2+1/2^3+1/2^4+……+1/2^99=1+1/2+1/2^2+1/2^3+1/2^4+……+1/2^99+1/2^99-1/2^99
1+1/2+1/2^2+1/2^3+1/2^4+……+1/2^98-1/2^99
1+1/2+1/2^2+1/2^3+1/2^4+……+1/2^97-1/2^99
=1+1/2+1/2-1/2^99
=2-1/2^99
或者是
1+1/2+1/2^2+1/2^3+1/2^4+……+1/2^99=1*[1-(1/2)^100]/(1-1/2)=2(1-1/2^100)