(1×6×9+2×12×18+3×18×27+.+100×600×900) /(1×6×9+2×12×18+3×18×27+.+100×600×900)/ (1×2×3+2×4×6+3×6×9+.+100×200×300)简便运算
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/28 03:59:44
![(1×6×9+2×12×18+3×18×27+.+100×600×900) /(1×6×9+2×12×18+3×18×27+.+100×600×900)/ (1×2×3+2×4×6+3×6×9+.+100×200×300)简便运算](/uploads/image/z/55233-9-3.jpg?t=%EF%BC%881%C3%976%C3%979%EF%BC%8B2%C3%9712%C3%9718%EF%BC%8B3%C3%9718%C3%9727%EF%BC%8B.%EF%BC%8B100%C3%97600%C3%97900%EF%BC%89+%2F%EF%BC%881%C3%976%C3%979%EF%BC%8B2%C3%9712%C3%9718%EF%BC%8B3%C3%9718%C3%9727%EF%BC%8B.%EF%BC%8B100%C3%97600%C3%97900%EF%BC%89%2F+%EF%BC%881%C3%972%C3%973%EF%BC%8B2%C3%974%C3%976%EF%BC%8B3%C3%976%C3%979%EF%BC%8B.%EF%BC%8B100%C3%97200%C3%97300%EF%BC%89%E7%AE%80%E4%BE%BF%E8%BF%90%E7%AE%97)
(1×6×9+2×12×18+3×18×27+.+100×600×900) /(1×6×9+2×12×18+3×18×27+.+100×600×900)/ (1×2×3+2×4×6+3×6×9+.+100×200×300)简便运算
(1×6×9+2×12×18+3×18×27+.+100×600×900) /
(1×6×9+2×12×18+3×18×27+.+100×600×900)/ (1×2×3+2×4×6+3×6×9+.+100×200×300)
简便运算
(1×6×9+2×12×18+3×18×27+.+100×600×900) /(1×6×9+2×12×18+3×18×27+.+100×600×900)/ (1×2×3+2×4×6+3×6×9+.+100×200×300)简便运算
(1×6×9+2×12×18+3×18×27+.+100×600×900)/ (1×2×3+2×4×6+3×6×9+.+100×200×300)
=1×6×9(1+2*2*2+3*3*3+.100*100*100)/1x2x3(1+2*2*2+3*3*3+.+100*100*100)
=1*6*9/1*2*3
=54/6
=9
1*6*9(1+2+3....+100)/1*2*3(1+2+3....+100)=6*9/2*3=9
观察法.除号前面每一项与后面的每一项对应是它的3*3倍.例如:1*6*9是1*2*3的9倍.则结果即为9.
=(1×6×9)×1+(1×6×9)×2的立方+(1×6×9)×3的立方......+(1×6×9)×100的立方/(1×2×3)×1+(1×2×3)×2的方立+(1×2×3)×3的立方+(1×2×3)×2的立方+(1×2×3)×3的立方.....+(1×2×3)×100的立方
=(1+6+9)(1+2的立方+3的立方.....100的立方)/(1×2×3)×(1+2的立方+3的立方......
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=(1×6×9)×1+(1×6×9)×2的立方+(1×6×9)×3的立方......+(1×6×9)×100的立方/(1×2×3)×1+(1×2×3)×2的方立+(1×2×3)×3的立方+(1×2×3)×2的立方+(1×2×3)×3的立方.....+(1×2×3)×100的立方
=(1+6+9)(1+2的立方+3的立方.....100的立方)/(1×2×3)×(1+2的立方+3的立方.....100的立方)
=1+6+9/1×2×3
=16/6
=8/3
满意吗?^^
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