H24

Giá trị của biểu thức: D=1-4+7-10...+307-310+313  là ?

TD
20 tháng 1 2016 lúc 5:00

sao ko giải ra giùm !!!

 

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TA
27 tháng 1 2016 lúc 19:23

157

 

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NH
22 tháng 3 2016 lúc 18:56

D=157 là 100% đấy, mình thử rồi

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LH
24 tháng 4 2016 lúc 9:05

Số số hạng của dãy trên là 

        ( 313 - 1 ):3+1=105 (số)

Trong 105 số có các cặp số như 1 - 4 ; 7 - 10;... đều có hiệu là (-3) và một số 313

Các cặp số có hiệu là (-3) : (105 - 1):2=52 (cặp)

Tổng của 52 cặp đó là: 52 . (-3)= -156

Tổng của dãy là (-156)+313 = 157 

Vậy tổng của dãy trên là 157

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H24
27 tháng 12 2016 lúc 20:47

157

ai tk mk

mk tk lại

hứa luôn

yên tâm

thank nhiều

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NH
28 tháng 12 2016 lúc 22:41

bang 157

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H24
31 tháng 12 2016 lúc 21:04

157 đó

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H24
4 tháng 1 2017 lúc 5:55

157 do ban

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NB
9 tháng 1 2017 lúc 11:13

157 là chuẩn 100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%

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VT
9 tháng 1 2017 lúc 12:24

157 đó bn!

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KM
16 tháng 1 2017 lúc 9:08

157chuan 100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%

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NM
19 tháng 1 2017 lúc 14:37

la 157 ay

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H24
20 tháng 1 2017 lúc 10:20

157 nha !

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H24
20 tháng 1 2017 lúc 10:32

157 nha !

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H24
20 tháng 1 2017 lúc 10:32

157 nha !

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PB
25 tháng 1 2017 lúc 17:30

157 mình chắc chắn 100% nếu sai tới nhà mình đốt

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H3
21 tháng 2 2017 lúc 21:44

157 đó bạn             

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H3
23 tháng 2 2017 lúc 21:04

là 157 hết 

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TH
27 tháng 2 2017 lúc 14:58

157 dễ quá iiiiii

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H24
19 tháng 3 2017 lúc 23:28

157 đó bạn chắc luôn 100% sai mình đưa cho bạn cái này luôn  

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NH
6 tháng 7 2017 lúc 13:57

D=175 làm sai tôi là con chó

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TQ
5 tháng 12 2017 lúc 23:43

Gọi D=1-4+7-10+.....+307-310+313

=>Số các số hạng của D là: (313-1):3+1=105 (SH)

=>D=1+(-4)+7+(-10)+.....+307+(-310)+313

    D=[1+(-4)]+[7+(-10)]+.....+[307+(-310)]+313

=>Có tất cả 52 cặp (dư 1 số - 313)

=>D=-3 + (-3) + ..... +(-3) + 313

                52 số hạng              

=>D=-(3.52)+313

    D=(-156)+313

    D=+(313-156)

=>D=      157

Vậy D = 157

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SD
20 tháng 2 2020 lúc 10:07

tổng dãy trên là 157.tk mình nha

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NK
10 tháng 3 2020 lúc 16:09

mình nhầm 

157 

nha mn

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H24

Gọi D=1-4+7-10+.....+307-310+313

D=[1+(-4)]+[7+(-10)]+.....+[307+(-310)]+313

=>Có tất cả 52 cặp (dư 1 số - 313)

=>D=-3 + (-3) + ..... +(-3) + 313

                52 số hạng              

=>D=-(3.52)+313

    D=(-156)+313

=>D=-(3.52)+313

    D=(-156)+313

    D=+(313-156)

=>D=157

Vậy D = 157

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