什么木的菜板好:计算这道题??

来源:百度文库 编辑:中科新闻网 时间:2024/05/05 14:20:14
(0.1+0.2+0.3+0.4+0.5)×(0.6+0.7+0.8+0.9+1)=?

6

(0.1+0.2+0.3+0.4+0.5)×(0.6+0.7+0.8+0.9+1)

=( 0.3 x 5 ) x ( 0.3 x 5 + 0.5 x 5 )

=( 1.5 ) x ( 1.5 + 2.5 )

= 1.5 x 4

= 6

★★★ 试试看:
(0.1+0.2+0.3+0.4+0.5)×(0.6+0.7+0.8+0.9+1)
=(0.1+0.5)×5×(0.6+1.0)×5/(2×2)
=0.6×5×1.6×5/4
=6

(2+1)*(2^2+1)*(2^4+1)*(2^8+1)*(2^16+1)
=(2-1)*(2+1)*(2^2+1)*(2^4+1)*(2^8+1)*(2^16+1)
=(2^2-1)*(2^2+1)*(2^4+1)*(2^8+1)*(2^16+1)
=2^31-1
=2147483647

A^2-B^2=(A+B)(A-B)

(0.1+0.2+0.3+0.4+0.5)×(0.6+0.7+0.8+0.9+1)= 1.5*4=6

(0.1+0.2+0.3+0.4+0.5)×(0.6+0.7+0.8+0.9+1)
=1.5×4
=6