1/2+3/6+5/10+7/4+9/18+11/12
=1/2+1/2+1/2+1/2+1/2+11/12
=5/2+11/12
=30/12+11/12
=41/12
1/2+3/6+5/10+7/4+9/18+11/12
=1/2+1/2+1/2+1/2+1/2+11/12
=5/2+11/12
=30/12+11/12
=41/12
1/2+2/3+3/4+4/5+5/6+6/7+7/8+8/9+9/10+10/11+11/12+12/13+13/14+14/15=?
Tính 1/2 + 3/6 + 5/10 + 7/14 + 9/18 + 11/12 = ......(nhập kết quả là số tự nhiên)
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20=?
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+...100=
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+.....+99999999999956214 (tính tỏng)
1+2-3-4+5+6-7-8+9+10-11-12+13+14-15-16+17+18-19-20...+301+302
Tính nhanh:
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19
tính : a) 2/3 *( 2/18+6/12-3/33 ) b) 6/14+4/25-5/10*3/16 c)5/25*(9/18+16/32-12/46) + 9/17 d)11/32:(14/18-16/27) + (2/3-5/15) e) ( 1/9+2/17)+3/6-(12/17-1/2) +5/9
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26=