Xin lỗi bạn vì mình gửi bài muộn ,mình đag pk trả lời câu khác
`( 1/2 -1/3-1/6). (1/2+2/3+3/4+.... 2017/2018)+3/4: x = 9/10`
`(3/6-2/6-1/6).(1/2+2/3+3/4+.... 2017/2018)+3/4:x=9/10`
`([3-2-1]/6)(1/2+2/3+3/4+.... 2017/2018)+3/4:x=9/10`
`0.(1/2+2/3+3/4+.... 2017/2018)+3/4:x=9/10`
`0+3/4:x=9/10`
`3/4:x+9/10`
`x=3/4:9/10`
`x=3/4. 10/9`
`x=5/6`
Vậy `x=5/6`
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