1/(1×2×3)+1/(2×3×4)+1/(3×4×5)+......+1/(9×10×11)

来源:学生作业帮助网 编辑:六六作业网 时间:2024/05/15 20:06:31
1/(1×2×3)+1/(2×3×4)+1/(3×4×5)+......+1/(9×10×11)1/(1×2×3)+1/(2×3×4)+1/(3×4×5)+......+1/(9×10×11)1/(1

1/(1×2×3)+1/(2×3×4)+1/(3×4×5)+......+1/(9×10×11)
1/(1×2×3)+1/(2×3×4)+1/(3×4×5)+......+1/(9×10×11)

1/(1×2×3)+1/(2×3×4)+1/(3×4×5)+......+1/(9×10×11)

1/(1×2×3)+1/(2×3×4)+1/(3×4×5)+......+1/(9×10×11)
=1/2×(1/1×2-1/2×3+1/2×3-1/3×4+……+1/9×10-1/10×11)
=1/2×(1/1×2-1/10×11)
=27/110