wow! mù mắt. Ido tính toán có khác!

C2:(32+1)x32:2=528

bạn tính thử xem đúng đấy.

A=15/8              D=27/40

B=4/15              E=1/14        

C=7/3                F=637/48

a: \(=3\cdot\left(\dfrac{1}{4}-\dfrac{6}{7}+\dfrac{8}{21}\right)\)

\(=3\cdot\left(\dfrac{21}{84}-\dfrac{72}{84}+\dfrac{32}{84}\right)\)

\(=\dfrac{-19}{28}\)

b: \(=\dfrac{-2}{3}\left(\dfrac{1}{9}-\dfrac{1}{6}-\dfrac{1}{11}\right)\)

\(=\dfrac{-2}{3}\cdot\dfrac{-29}{198}=\dfrac{29}{99\cdot3}=\dfrac{29}{297}\)

c: \(=\dfrac{-3}{7}+\dfrac{4}{25}+\dfrac{5}{16}+\dfrac{3}{16}\)

\(=\dfrac{-75+28}{175}+\dfrac{1}{2}\)

\(=\dfrac{-47}{175}+\dfrac{1}{2}=\dfrac{-94+175}{350}=\dfrac{81}{350}\)

d: \(=\dfrac{-4}{9}\cdot\left(\dfrac{1}{26}-\dfrac{1}{2}-\dfrac{1}{8}\right)\)

\(=\dfrac{-4}{9}\cdot\dfrac{-61}{104}=\dfrac{61}{26\cdot9}=\dfrac{61}{234}\)

bạn ơi cho mk hỏi đề bài yêu cầu j thế ak

5) 43/45 và 61/63 gần bằng 1 ( 45/45 hoặc 63/63)

45/45-43/45=2/45

63/63-61/63=2/63

Vì 43/45 kém 45/45 là 2/45

Còn 61/63 kém 63/63 là 2/63

2/45>2/65 => 43/45<63/65

6) tương tự con 5)

7) bó tay

8) bó tay

9) lấy phân số trung gian là 16/91

16/45 <16/91<23/91

=> 16/45 <23 /91

10) bó tay

BÀI 1

a,  \(5\times\frac{-7}{10}=\frac{-35}{10}=\frac{-7}{2}\)

b,  \(\frac{4}{5}\times\frac{-7}{10}=\frac{-28}{50}=\frac{-14}{25}\)

c,  \(\frac{4}{9}+\frac{4}{3}\times\frac{16}{4}=\frac{4}{9}+\frac{16}{3}=\frac{52}{9}\)

d,  \(\frac{11}{22}-\frac{3}{9}\times\frac{14}{21}=\frac{11}{22}-\frac{2}{9}=\frac{55}{198}=\frac{5}{18}\)  

BÀI 2

\(A=\frac{6}{13}\times\frac{5}{7}+\frac{6}{13}\times\frac{2}{7}+\frac{17}{13}\)

\(A=\frac{30}{91}+\frac{12}{91}+\frac{17}{13}\)

\(A=\frac{30}{91}+\frac{12}{91}+\frac{119}{91}\)

\(A=\frac{161}{91}=\frac{23}{13}\)

\(B=\frac{11}{15}\times\frac{4}{11}+\frac{11}{15}\times\frac{5}{11}+\frac{11}{15}\times\frac{2}{11}\)

\(B=\frac{4}{15}+\frac{1}{3}+\frac{2}{15}\)

\(B=\frac{11}{15}\)

\(C=\left(\frac{19}{64}-\frac{33}{22}+\frac{24}{51}\right)\times\left(\frac{1}{5}-\frac{1}{15}-\frac{2}{15}\right)\)

\(C=\frac{-797}{1088}\times0\)

\(C=0\)

\(D=\frac{8}{13}\times\frac{7}{12}+\frac{8}{13}\times\frac{5}{12}-\frac{1}{12}\)

\(D=\frac{14}{39}+\frac{10}{39}-\frac{1}{12}\)

\(D=\frac{83}{156}\)

bạn biết câu náy không (24 + 11) . {546 - [14 . (64 - 2^{3}3) : 2]} =

a) \(33^4=\left(3.11\right)^4=3^4.11^4\\ 44^3=\left(4.11\right)^3=4^3.11^3\)

Ta thấy 3⁴>4³ và 11⁴>11³ nên 33⁴>44³

c) \(54^4=\left(3.18\right)^4=3^4.18^4=3^4.\left(2.9\right)^4=3^4.9^4.2^4=27^4.2^4\\ 21^{12}=\left(3.7\right)^{12}=3^{12}.7^{12}=\left(3^3\right)^4.7^{12}=27^4.7^{12}\)

Ta so sánh 2⁴ với 7¹²

\(7^{12}=\left(7^3\right)^4\)

Nhìn vào ta thấy 2<7³ => 2⁴<7¹²=> 54⁴<21¹²

a: Ta có: \(A=\frac59+\left(-\frac57\right)+\left(-\frac{20}{48}\right)+\frac{8}{12}+\left(-\frac{21}{48}\right)\)

\(=\frac59-\frac57-\frac{41}{48}+\frac{32}{48}\)

\(=\frac{35-45}{63}-\frac{9}{48}=\frac{-10}{63}-\frac{3}{16}=\frac{-160-189}{63\cdot16}=\frac{-349}{1008}\)

b: \(B=\left(-\frac59\right)+\frac{8}{15}+\left(-\frac{2}{11}\right)+\left(\frac{4}{-9}\right)+\frac{2}{45}\)

\(=\left(-\frac59-\frac49\right)+\frac{8}{15}+\frac{2}{45}-\frac{2}{11}\)

\(=-1-\frac{2}{11}+\frac{24}{45}+\frac{2}{45}=-\frac{13}{11}+\frac{26}{45}=\frac{-13\cdot45+26\cdot11}{11\cdot45}=\frac{-299}{495}\)

c: \(\frac{1}{11}>\frac{1}{20};\frac{1}{12}>\frac{1}{20};\ldots;\frac{1}{20}=\frac{1}{20}\)

Do đó: \(\frac{1}{11}+\frac{1}{12}+\cdots+\frac{1}{20}>\frac{1}{20}+\frac{1}{20}+\cdots+\frac{1}{20}\)

=>S>10/20

=>S>1/2

1:

a, 8⁵ và 3 . 4⁷ , 8⁵

Mà 8⁵ = 8⁵ ; 3 . 4⁷ > 1

=> 8⁵ < 3 . 4⁷ . 8⁵

b, 54⁴ và 21¹²

54⁴ = ( 54 : 3 )¹² = 18¹²

Mà 18¹² < 21¹²

=> 54⁴ < 21¹² 

a, 8⁵ và 3 . 4⁷ , 8⁵

Mà 8⁵ = 8⁵ ; 3 . 4⁷ > 1

=> 8⁵ < 3 . 4⁷ . 8⁵

b, 54⁴ và 21¹²

54⁴ = ( 54 : 3 )¹² = 18¹²

Mà 18¹² < 21¹²

=> 54⁴ < 21¹²