1/5=1/( )-1/( )-1/( ) 求这题用什么方法解答

1+1+1+1+1+1+1×5=? (1/7.5+1/5)+1/5(x-1)=1 1+1+1+1+0+1 1+4+1+1+1+1 0+1+1*5-5=? 1+1+1+1+1+1+1+1+1×5×0+50= (1+1/2)*(1-1/2)*(1+1/3)*(1-1/3)*(1+1/4)*(1-1/4)*(1+1/5)*(1-1/5)=? 5/1x-2/1=1 （1+x)(1-5%)=1+14% 巧算：(1+1/2+1/3+1/4+1/5)*(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)*(1/2+1/3+1/4+1/5)(1+1/2+1/3+1/4+1/5)*(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)*(1/2+1/3+1/4+1/5)===== 1/7.5+1/5+1/5*X=1 1-1/2+1/3-1/4+1/5-1/6+1/7.-1/50=? 1-1/2+1/3-1/4+1/5-1/6+…+1/15=23*[1/( )+1/( )+1/( )+1/( )] 口算 1/4+1/5= 1/5+1/8= 1/4-1/6= 一道无聊数学题,谁答最快选谁1-1-1-1-1-1-1-1-1-1-1-1-1-1-1-1-1-2-5-5-5-5-8-62-5-5-5-4-5-6=? 数学题(1/4+1/5+1/6+...+1/671)(1/3+1/4+1/5+..+1/670)-(1/3+1/4+1/5+...+1/671)(1/4+1/(1/4+1/5+1/6+...+1/671)(1/3+1/4+1/5+..+1/670)-(1/3+1/4+1/5+...+1/671)(1/4+1/5+1/6+...+1/670）=? (1/3+1/5+1/7)*(1/5+1/7+1/9)-(1/3+1/5+1/7+1/9)*(1/5+1/7)=? 1+1+1=? (1-1/2)(1/3-1)(1-1/4)(1/5-1)…(1-1/50)= 1+1+1-1=?.