\(A=\frac{\left(23\frac{11}{15}-26\frac{13}{20}\right)}{12^2+5^2}\cdot\frac{1-\frac{1}{30}-\frac{1}{42}-\frac{1}{56}}{3^2.13.2-13.5}-\frac{19}{37}\)

\(A=\frac{\left(23+\frac{11}{15}-26+\frac{13}{20}\right)}{144+25}\cdot\frac{1-\frac{1}{5.6}-\frac{1}{6.7}-\frac{1}{7.8}}{9.13.2-13.5}-\frac{19}{37}\)

\(A=\frac{\left(23+26+\frac{11}{15}-\frac{13}{20}\right)}{169}\cdot\frac{1-\left(\frac{1}{5}-\frac{1}{6}\right)-\left(\frac{1}{6}-\frac{1}{7}\right)-\left(\frac{1}{7}-\frac{1}{8}\right)}{13.\left(9.2-5\right)}-\frac{19}{37}\)

\(A=\frac{49+\frac{44}{60}-\frac{39}{60}}{169}\cdot\frac{1-\frac{1}{5}+\frac{1}{6}-\frac{1}{6}+\frac{1}{7}-\frac{1}{7}+\frac{1}{8}}{13.13}-\frac{19}{37}\)

\(A=\frac{49+\frac{1}{20}}{169}\cdot\frac{1-\frac{1}{5}+\frac{1}{8}}{169}-\frac{19}{37}\)

\(A=\frac{49\frac{1}{20}}{169}\cdot\frac{\frac{4}{5}+\frac{5}{40}}{169}-\frac{19}{37}\)

\(A=\frac{981}{169}\cdot\frac{\frac{32}{40}+\frac{5}{40}}{169}-\frac{19}{37}\)

\(A=\frac{981}{169}\cdot\frac{\frac{37}{40}}{169}-\frac{19}{37}\)

\(A=\frac{981.\frac{37}{40}}{169^2}-\frac{19}{37}\)

\(A=\frac{\frac{36297}{40}}{28561}-\frac{19}{37}\)

\(A=\frac{907,425}{28561}-\frac{19}{37}\)

\(A=\frac{33574,725}{1056757}-\frac{542659}{1056757}\)

\(A=\frac{-509084,275}{1056757}=-0,04604282...\)

Mik chỉ làm đc thế này thôi, ôn thi học kì II tốt nha bạn!

B) (-11)+350+16+(-350 )

= - 11 + 350 + 16 - 350 )

= ( - 11 + 16 ) + ( 350 - 350 )

= 5 + 0 =5

C) (-10)+23+(-20)+30

= - 10 + 23 - 20 + 30

= ( - 10 - 20 + 30 ) + 23

= - 30 + 30 + 23

= 0 + 23 = 23

D) (456-123)+123

= 456 - 123 + 123 

= 456 

E) (-102)-(345-102)

= - 102 - 345 + 102

= ( - 102 + 102 ) - 345

= 0 - 345

= - 345

F) (12-34)-(34-8)

=  12 - 34  - 34 - 8

= (12 - 8 ) + ( -34 - 34 )

= 4 - 68 

= 64

 G) (12+34-56)-(12-56)

= 12 + 34 - 56 - 12 +56

= ( 12 - 12 ) + ( -56 + 56 ) + 34

= 0 + 0 + 34

= 34

Câu F k giống tính nhanh ____ Có thể là bạn gõ sai đề

@@ Học tốt @@
## Chiyuki Fujito

b ) (-11) + 350 + 16 + (-350) 

= (16 - 11 ) + ( 350 - 350 ) 

= 5 + 0 

= 5 

c)  (-10) + 23 + (-20) + 30

= 23 + ( 30 - 10 - 20 )

= 23 + 0 

= 23

d) ( 456 - 123 ) + 123

= 456 - ( 123 - 123 )

= 456 - 0 

= 456

e)  ( - 102 ) - ( 345 - 102 )

= - 345 - ( 102 - 102 ) 

= - 345 - 0 

= - 345

B) (-11)+350+16+(-350 )

= - 11 + 350 + 16 - 350 )

= ( - 11 + 16 ) + ( 350 - 350 )

= 5 + 0 =5

C) (-10)+23+(-20)+30

= - 10 + 23 - 20 + 30

= ( - 10 - 20 + 30 ) + 23

= - 30 + 30 + 23

\(M=\frac{1}{2}+\frac{5}{6}+...+\frac{89}{90}=1-\frac{1}{2}+1-\frac{1}{6}+...+1-\frac{1}{90}\)

\(=9-\left(\frac{1}{2}+\frac{1}{6}+...+\frac{1}{90}\right)\)

\(=9-\left(\frac{1}{1.2}+\frac{1}{2.3}+...+\frac{1}{9.10}\right)\)

\(=9-\left(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{9}-\frac{1}{10}\right)\)

\(=9-\left(1-\frac{1}{10}\right)\)

\(=8+\frac{1}{10}\)

\(=\frac{81}{10}\)

cái này lớp 5 mk  cx làm được,81/10 chắc

hoàng tử bấm máy tính chứ gì?

\(=\frac{8}{10}\)

\(M=\frac{1}{2}+\frac{5}{6}+...+\frac{89}{90}=1-\frac{1}{2}+1-\frac{1}{6}+...+1-\frac{1}{90}\)

\(=9-\left(\frac{1}{2}+\frac{1}{6}+...+\frac{1}{90}\right)\)

\(=9-\left(\frac{1}{1.2}+\frac{1}{2.3}+...+\frac{1}{9.10}\right)\)

\(=9-\left(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{9}-\frac{1}{10}\right)\)

\(=9-\left(1-\frac{1}{10}\right)\)

\(=8+\frac{1}{10}\)

\(=\frac{81}{10}\)

12 + 34 + 56 + 1 + 23 = 126

12 + 34+56+1+23= 34+56+12+1+23=90+13+23=103+23=126

lộn 126

\(a)3784+23-3785-15\)

\(= \left(3784-3785\right)+\left(23-15\right)\)

\(=-1+8=7\)

\(b)21+22+23+24-11-12-13-14\)

\(=\left(21-11\right)+\left(22-12\right)+\left(23-13\right)+\left(24-14\right)\)

\(=10+10+10+10=40\)

a)3784+23-3785-15=(3784-3785)+(23-15)=(-1)+8=7

b)21+22+23+24-11-12-13-14=(21-11)+(22-12)+(23-13)+(24-14)

=10+10+10+10=4X10=40

Học tốt

Âm 1 thì phải

tui con nho maaaaaaaa

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