1/(1+√2)+1/(√2+√3)+1/(√3+2)+.+1/(3+√10)=

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1/(1+√2)+1/(√2+√3)+1/(√3+2)+.+1/(3+√10)=
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1/(1+√2)+1/(√2+√3)+1/(√3+2)+.+1/(3+√10)=
1/(1+√2)+1/(√2+√3)+1/(√3+2)+.+1/(3+√10)=

1/(1+√2)+1/(√2+√3)+1/(√3+2)+.+1/(3+√10)=
分母有理化,=(√2-1)+(√3-√2)+(√4-√3)+...+(√10-√9)=√10-1.

因为1/1+√2=√2-1,1/(√2+√3)=√3-√2。所以原式=√2-1+√3-√2+…+√10-3=√10-1

将每一项都分母有理化得
1/(1+√2)=√2-1
1/(√2+√3)=√3-√2
.......
1/(3+√10)= √10-3
则原式=√2-1+√3-√2+.....+√10-3=√10-1