化简:(1-1/2²)(1-1/3²)(1-1/4²)...(1-1/99²)(1-1/100²)

来源:学生作业帮助网 编辑:作业帮 时间:2024/04/29 07:29:52
化简:(1-1/2²)(1-1/3²)(1-1/4²)...(1-1/99²)(1-1/100²)

化简:(1-1/2²)(1-1/3²)(1-1/4²)...(1-1/99²)(1-1/100²)
化简:(1-1/2²)(1-1/3²)(1-1/4²)...(1-1/99²)(1-1/100²)

化简:(1-1/2²)(1-1/3²)(1-1/4²)...(1-1/99²)(1-1/100²)
=(2²-1)/2²(3²-1)/3²(4²-1)/4²...(99²-1)/99²(100²-1)/100²
=(2-1)(2+1)/2²(3-1)(3+1)/3²(4-1)(4+1)/4²...(99-1)(99+1)/99²(100-1)(100+1)/100²
=(1·3)/2²(2·4)/3²(3·5)/4²...(98·100/99²(99·101)/100²
=1/2·101/100=101/200

(1-1/2²)(1-1/3²)(1-1/4²)...(1-1/99²)(1-1/100²)
=(1-1/2)(1+1/2)(1-1/3)(1+1/3)(1-1/4)(1+1/4).......(1-1/99)(1+1/99)(1-1/100)(1+1/100)
=1/2*3/2*2/3*4/3*3/4*5/4*............*98/99*100/99*99/100*101/100
=1/2*101/100
=101/200