急:试求(1-1/2^2)(1-1/3^2)(1-1/4^2)……(1-1/10^2)的值

来源:百度知道 编辑:UC知道 时间:2024/06/28 03:50:15

(1-1/2^2)(1-1/3^2)(1-1/4^2)……(1-1/10^2)
=(1-1/2)(1+1/2)(1-1/3)(1+1/3)……(1-1/10)(1+1/10)
=(1/2)(3/2)(2/3)(4/3)(3/4)(5/4)……(9/10)(11/10)
中间的都约分约掉了
=(1/2)*(11/10)
=11/20

(1-1/2^2)(1-1/3^2)(1-1/4^2)……(1-1/10^2)
=(1+1/2)(1-1/2)(1+1/3)(1-1/3)(1+1/4)(1-1/4).....+(1+1/10)(1-1/10)
=3/2×1/2×4/3×2/3×5/4×3/4...11/10×9/10
=1/2×11/10
=11/20

解:原式=(1-1/2)X(1+1/2)X(1-1/3)X(1+1/3)…(1-1/9)X(1+1/9)X(1-1/10)
=1/2 X 3/2 X 2/3 X 4/3 … 8/9X10/9X9/10X11/10
=1/2X11/10
=11/20
这是我今天早上数学评价手册P52页上才写的 老师改过了 是对的0.0

(1-1/2^2)(1-1/3^2)(1-1/4^2)...(1-1/10^2)
=(1-1/2)(1+1/2)(1-1/3)(1+1/3)...(1-1/10)(1+1/10)
=(1/2)(3/2)(2/3)(4/3)(3/4)(5/4)...(9/10)(11/10)
=(1/2)(11/10)
=11/20

(1-1/2^2)(1-1/3^2)(1-1/4^2)……(1-1/10^2)
=(1+1/2)(1-1/2)(1+1/3)(1-1/3)(1+1/4)(1-1/4).....+(1+1/10)(1-1/10)
=3/2*1/2*4/3*2/3*5/4*3/4...11/10*9/10
=1/2*11/10
=11/20

(1-1/2^2)(