1/1*2+1/2*3+1/3*4+…+1/49*50
巧算1/1×2+1/2×3+1/3×4+…1/49×50
1/2×3+1/3×4+1/4×5+……+1/49×50
计算(50/1)(49/1)(48/1)…(4/1)(3/1)(2/1)的值
1/2*3+1/3*4+1/4*5……+1/48*49+1/49*50是多少
2×1/1+2×3/1+3×4/1+4×5/1+……49×50/1怎么解?
奥数题1+2+3+4+……+49+50
求1/2+(3/1+2/3)+(1/4+2/4+3/4)+……+(1/50+2/50+3/50+……+48/50+49/
1*2+2*3+3*4+4*5+5*6+……48*49+49*50
1*2分之1+2*3分之1+3*4分之1+……到49*50分之1
计算1/1*2 +1/2*3 +1/3*4 +……+1/49*50 (“/”为分数线,“*”为乘号)
巧算:50-49+48-47+…+4-3+2-1
1+2+3+……48+49+50+49+48+……+3+2+1