1/2+5/6+11/12+19/20+29/30+41/42+55/56+71/72+89/90 10/08/2021 Bởi Ariana 1/2+5/6+11/12+19/20+29/30+41/42+55/56+71/72+89/90
1/Đáp án: 8110Giải thích các bước giải: 1/2+56+11/12+19/20+29/30+41/42+55/56+71/72+89/90 =1-1/2+1-16+1-112+1-120+1-130+1-142+1-156+1-172+1-190 =9–(12+16+112+120+130+142+156+172+190) =9–[11.2+12.3+13.4+14.5+15.6+16.7+17.8+18.9+19.10] =9–(1-12+12-13+13-14+14-15+15-16+16-17+17-18+18-19+19-110) =9–(1–110)=9–910=8110.2+ Bình luận
1/2 + 5/6 + 11/12 + 19/20+ 29/30 +41/42+55/56+71/72+89/90 = 1 -1/2 +1-1/6+1- 1/12+1-1/20 + 1-1/30+1-1/42+ 1-1/56+1-1/72+1-1/90 =(1+1+1+1+1+1+1+1+1)-(1/1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7- 1/8+1/8-1/9+1/9-1/10) =9-(1 -1/10) =9-9/10 =81/10 Bình luận
1/Đáp án:
8110
Giải thích các bước giải:
1/2+56+11/12+19/20+29/30+41/42+55/56+71/72+89/90
=1-1/2+1-16+1-112+1-120+1-130+1-142+1-156+1-172+1-190
=9–(12+16+112+120+130+142+156+172+190)
=9–[11.2+12.3+13.4+14.5+15.6+16.7+17.8+18.9+19.10]
=9–(1-12+12-13+13-14+14-15+15-16+16-17+17-18+18-19+19-110)
=9–(1–110)=9–910=8110.2+
1/2 + 5/6 + 11/12 + 19/20+ 29/30 +41/42+55/56+71/72+89/90
= 1 -1/2 +1-1/6+1- 1/12+1-1/20 + 1-1/30+1-1/42+ 1-1/56+1-1/72+1-1/90
=(1+1+1+1+1+1+1+1+1)-(1/1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7- 1/8+1/8-1/9+1/9-1/10)
=9-(1 -1/10)
=9-9/10
=81/10