求(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128,请问可以套用哪种列项公式,看得有点糊涂,请提供裂项公式!
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![求(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128,请问可以套用哪种列项公式,看得有点糊涂,请提供裂项公式!](/uploads/image/z/317365-61-5.jpg?t=%E6%B1%82%281%2F8%2B1%2F24%2B1%2F48%2B1%2F80%2B1%2F120%2B1%2F168%2B1%2F224%2B1%2F288%29%2A128%2C%E8%AF%B7%E9%97%AE%E5%8F%AF%E4%BB%A5%E5%A5%97%E7%94%A8%E5%93%AA%E7%A7%8D%E5%88%97%E9%A1%B9%E5%85%AC%E5%BC%8F%2C%E7%9C%8B%E5%BE%97%E6%9C%89%E7%82%B9%E7%B3%8A%E6%B6%82%EF%BC%8C%E8%AF%B7%E6%8F%90%E4%BE%9B%E8%A3%82%E9%A1%B9%E5%85%AC%E5%BC%8F%EF%BC%81)
求(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128,请问可以套用哪种列项公式,看得有点糊涂,请提供裂项公式!
求(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128,请问可以套用哪种列项公式,
看得有点糊涂,请提供裂项公式!
求(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128,请问可以套用哪种列项公式,看得有点糊涂,请提供裂项公式!
[1/(2x4)+1/(4x6)+1/(6x8)+……+1/(16x18)]x128
=1/4x(1-1/2+1/2-1/3+……+1/8-1/9)x128
=1/4x8/9x128
=256/9
(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128
=(1/2*4+1/4*6+1/6*8+...+1/16*18)*128
=1/2*(1/2-1/4+1/4-1/6+1/6-1/8+.....+1/16-1/18)*128
=1/2*(1/2-1/18)*128
=1/2*7/18*128
=224/9