Có số số hạng là: (69 - 6) : 3 + 1 = 22 (số)

S = (69 + 6) x 22 : 2 = 825

Ý bạn là mỗi phép tính phải thêm dấu và ....để kết quả bằng 6 phải không ạ

(1+1+1)×2=6

2+2+2=6

3×3⁰+3=6

(4+4+4)÷2=6

(5⁰+5⁰+5⁰)×2=6

6×6⁰×6⁰=6

7-7⁰×7⁰=6

8-(8⁰+8⁰)=6

(9⁰+9⁰+9⁰)×2=6

(10⁰+10⁰+10⁰)×2=6

Bài 1 :

a) 37581 - 9999 = 37581 - 10000 - 1 = 27581 - 1 = 27580

k cho mình nha bạn ! 

a)37581-9999=37581-(9999+1-1)=37581-(10000+1)=37581-10000-1=27581+1=27582

đó là phần tính nhanh mong các bạn nha!

6: =>x=9/10+1/5=9/10+2/10=11/10

7: =>x=3/8-5/12=36/96-40/96=-1/24

8: =>x=7/6-5/4=14/12-15/12=-1/12

9: =>x=1/35+2/7=1/35+10/35=11/35

10: =>x=2/7-7/10=20/70-49/70=-29/70

1, \(x=-\dfrac{5}{3}-\dfrac{1}{2}=-\dfrac{10}{6}-\dfrac{3}{6}=-\dfrac{13}{6}\)

2, \(x=\dfrac{1}{3}-\dfrac{3}{5}=\dfrac{5-9}{15}=-\dfrac{4}{15}\)

4, \(x=-\dfrac{7}{9}+\dfrac{4}{3}=\dfrac{-7+12}{9}=\dfrac{5}{9}\)

5, \(x=\dfrac{5}{6}-\dfrac{7}{3}=\dfrac{5-14}{6}=-\dfrac{9}{6}=-\dfrac{3}{2}\)

6, \(x=\dfrac{9}{10}+\dfrac{1}{5}=\dfrac{9+2}{10}=\dfrac{11}{10}\)

7, \(x=\dfrac{3}{8}-\dfrac{5}{12}=\dfrac{9-10}{12}=-\dfrac{1}{12}\)

8, \(x=\dfrac{7}{6}-\dfrac{5}{4}=\dfrac{14-15}{12}=-\dfrac{1}{12}\)

9, \(x=\dfrac{1}{35}+\dfrac{2}{7}=\dfrac{1+10}{35}=\dfrac{11}{35}\)

10, \(x=-\dfrac{7}{10}+\dfrac{2}{7}=\dfrac{-49+20}{70}=\dfrac{-29}{70}\)

a ) bằng 0.

b ) bằng 65.

a. (45-63+18) x (1+2+3+4+5+6+7+8+9)

= 0 x (1+2+3+4+5+6+7+8+9) = 0

b. 60-61+62-63+64-65+66-67+68-69+70

= 60 + (-61-69)+(62+68)+(-63-67)+(64+66)-65+70

= 60 + (-130)+130+(-130)+130-65-70

= 60 + (-130+130) + (-130+130)-65+70

= 60 - 65 + 70 = 65

Zui lòng chia nhỏ

1: =>x=-5/3-1/2=-13/6

2: =>x=1/3-3/5=-4/15

4: =>x=-7/9+4/3=-7/9+12/9=5/9

5: =>x=5/6-7/3=5/6-14/6=-9/6=-3/2

6: =>x=9/10+1/5=11/10

7: =>x=3/8-5/12=36/96-40/96=-1/24

8: Đề sai rồi bạn

Mình nghĩ đề đúng là :

\(\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)

\(=\frac{2^{12}.3^{10}+2^9.3^9.3.5.2^3}{2^{12}.3^{12}-2^{11}.3^{11}}\)

\(=\frac{2^{12}.3^{10}+2^{12}.3^{10}.5}{2^{12}.3^{12}-2^{11}.3^{11}}\)

\(=\frac{2^{12}.3^{10}\left(1+5\right)}{2^{11}.3^{11}.\left(2.3-1\right)}\)

\(=\frac{2^{12}.3^{10}.6}{2^{11}.3^{11}.5}\)

\(=\frac{2^{13}.3^{11}}{2^{11}.3^{11}.5}\)

\(=\frac{2^2}{5}\)

\(=\frac{4}{5}\)