上海万象城入驻品牌:数学简算哦~~~~~~~~~~~~!

来源:百度文库 编辑:中科新闻网 时间:2024/05/13 11:19:57
1X3X5+2X6X10+3X9X15+……+50X150X250
—————————————————— 分数线
2X4X6+4X6X8+6X12X18+……+100X200X300
简算哦!写出过程,谢谢!!

分数线上面:(1*3*5)*(1+2+3+……+50)
分数线下面:(2*4*6)*(1+2+3+……+50)
所以就等于:1*3*5/(2*4*6)=15/48=5/16

1X3X5+2X6X10+3X9X15+……+50X150X250
——————————————————
2X4X6+4X6X8+6X12X18+……+100X200X300

1X3X5+2^3X1X3X5+3^3X1X3X5+……+50^3X1X3X5
=—————————————————————
2X4X6+2^3X2X4X6+3^3X2X4X6+……+50^3X2X4X6

1X3X5(1+2^3+3^3+……+50^3)
=——————————————
2X4X6(1+2^3+3^3+……+50^3)

1X3X5
=———
2X4X6

5
=—
16

(1+2+3+...50)*(1*3*5) 1*3*5 15
= ---------------------- = ----- = -----
(1+2+3+...50)*(2*4*6) 2*4*6 48