a)   8 . 4^5  - 3 . 9 . 12 + 28 : 4 . 2^0 = 7875

b)   210 + 86 . 2^3  : 2 - 19 . 23 = 117

c)   144 .12 + 83 . 11 - 17 . 3 = 2590

d)   54 . 23 + 11^2 - 152 = 1211

a) 8 . 4⁵ - 3 . 9 . 12 + 28 : 4 . 2⁰ = 7875

b) 210 + 86 . 2³ : 2 - 19 . 23 = 117

c) 144 . 12 + 83 . 11 - 17 . 3 = 2590

d) 54 . 23 + 11² - 152 = 1211

a: =8-6=2

b: =30(55+46-1)=3000

a) 8 + 2. ( − 3 ) = 8 + ( - 6 ) = 8 - 6 = 2 
b) 30.55 + 30.46 – 2.15

= 30 . 55 + 30 . 46 - 30

= 30 . ( 55 + 46 - 1 )

= 30 . 100 = 3000
c) 4.15 − [ 144 − ( 12 − 4 )² ]

= 4 . 15 - [ 144 - 8² ]

= 4 .15 - [ 144 - 64 ] 

= 60 - 80

= - 20

a) \(\dfrac{-5}{9}+\dfrac{8}{15}+\dfrac{-2}{11}+\dfrac{4}{-9}+\dfrac{7}{15}\)

=\(\left(\dfrac{-5}{9}+\dfrac{-4}{9}\right)+\left(\dfrac{8}{15}+\dfrac{7}{15}\right)+\dfrac{-2}{11}\)

=\(\left(-1\right)+1+\dfrac{-2}{11}\)

=\(\dfrac{-2}{11}\)

b) \(\left(\dfrac{-5}{12}+\dfrac{6}{11}\right)+\left(\dfrac{7}{17}+\dfrac{5}{11}+\dfrac{5}{12}\right)\)

=\(\dfrac{-5}{12}+\dfrac{6}{11}+\dfrac{7}{17}+\dfrac{5}{11}+\dfrac{5}{12}\)

=\(\left(\dfrac{-5}{12}+\dfrac{5}{12}\right)+\left(\dfrac{6}{11}+\dfrac{5}{11}\right)+\dfrac{7}{17}\)

=\(0+0+\dfrac{7}{17}\)

=\(\dfrac{7}{17}\)

c) A= \(49\dfrac{8}{23}-\left(5\dfrac{7}{32}+14\dfrac{8}{23}\right)\)

A=\(49\dfrac{8}{23}-5\dfrac{7}{32}-14\dfrac{8}{23}\)

A=\(\left(49\dfrac{8}{23}-14\dfrac{8}{23}\right)-5\dfrac{7}{32}\)

A=\(35-5\dfrac{7}{32}\)

A=\(35-\dfrac{167}{32}=\dfrac{953}{32}\)

d) C=\(\dfrac{-3}{7}.\dfrac{5}{9}+\dfrac{4}{9}.\dfrac{-3}{7}+2\dfrac{3}{7}\)

C=\(\dfrac{-3}{7}.\left(\dfrac{5}{9}+\dfrac{4}{9}\right)+\dfrac{17}{7}\)

C=\(\dfrac{-3}{7}.1+\dfrac{17}{7}\)

C=\(\dfrac{-3}{7}+\dfrac{17}{7}=2\)

a, `(-5)/9+8/15+(-2)/11+4/(-9)+7/15`

`=-5/9+8/15-2/11-4/9+7/15`

`=(-5/9-4/9)+(8/15+7/15)-2/11`

`=-9/9+15/15-2/11`

`=-1+1-2/11`

`=-2/11`

b, `((-5)/12+6/11)+(7/17+5/11+5/12)`

`=-5/12+6/11+7/17+5/11+5/12`

`=(-5/12+5/12)+(6/11+5/11)+7/17`

`=0+11/11+7/17`

`=1+7/17`

`=17/17+7/17`

`=24/17`

c, `A=49 8/23 - (5 7/32 + 14 8/23)`

`A=49 8/23 - 5 7/32 - 14 8/23`

`A=(49 8/23 - 14 8/23)-5 7/32`

`A=35 - 167/32`

`A=953/32`

d, `C=(-3)/7.5/9+4/9.(-3)/7+2 3/7`

`C=-3/7 . 5/9-4/9 . 3/7+17/7`

`C=-3/7.(5/9+4/9)+17/7`

`C=-3/7 . 1+17/7`

`C=2`

a) Ta có: \(\dfrac{-5}{9}+\dfrac{8}{15}+\dfrac{-2}{11}+\dfrac{-4}{9}+\dfrac{7}{15}\)

\(=\left(\dfrac{-5}{9}+\dfrac{-4}{9}\right)+\left(\dfrac{8}{15}+\dfrac{7}{15}\right)-\dfrac{2}{11}\)

\(=-1+1-\dfrac{2}{11}\)

\(=-\dfrac{2}{11}\)

b) Ta có: \(\left(\dfrac{-5}{12}+\dfrac{6}{11}\right)+\left(\dfrac{7}{11}+\dfrac{5}{11}+\dfrac{5}{12}\right)\)

\(=\left(\dfrac{-5}{12}+\dfrac{5}{12}\right)+\left(\dfrac{6}{11}+\dfrac{7}{11}+\dfrac{5}{11}\right)\)

\(=\dfrac{18}{11}\)

c) Ta có: \(A=49\dfrac{8}{23}-\left(5\dfrac{7}{32}+14\dfrac{8}{23}\right)\)

\(=49+\dfrac{8}{23}-14-\dfrac{8}{23}-5-\dfrac{7}{32}\)

\(=30-\dfrac{7}{32}=\dfrac{953}{32}\)

Bạn ơi, bạn viết lại đề đi. Khó nhìn quá

a) 49 - 9 . [ 3⁴ : 3¹ - ( 12 - 4 ) : 2²  ]

= 49 - 9 . [ 3³ - 8 : 2² ]

=  49 - 9 . [ 3³ -2³ : 2² ]

=  49 - 9 . [ 3³ - 2 ]

= 49 - 9 . [ 27 - 2 ]

= 49 - 9 . 25

= 49 - 225 = -176

b) 4.5² + 16 : 2²

= 4. 25 + 2⁴ : 2²

= 100 + 2² = 100+ 4 =104

--tho--là tớ💋

c) 5³ : 5 - 2017⁰

= 5² - 1 = 25 - 1= 24 

d) 2² . 3 - ( 10⁰ + 8 ) : 3²

= 4. 3 - ( 1 + 8 ) : 3²

= 4. 3 - 9 : 3²

= 12 - 3² : 3²

= 12 - 1 = 11.

--tho--là tớ💋

a: \(\dfrac{8}{18}+\dfrac{5}{3}=\dfrac{4}{9}+\dfrac{5}{3}=\dfrac{4}{9}+\dfrac{15}{9}=\dfrac{4+15}{9}=\dfrac{19}{9}\)

b: \(\dfrac{8}{24}+\dfrac{4}{48}=\dfrac{1}{3}+\dfrac{1}{12}=\dfrac{4}{12}+\dfrac{1}{12}=\dfrac{4+1}{12}=\dfrac{5}{12}\)

c: \(\dfrac{20}{15}-\dfrac{4}{45}=\dfrac{4}{3}-\dfrac{4}{45}=\dfrac{60}{45}-\dfrac{4}{45}=\dfrac{60-4}{45}=\dfrac{56}{45}\)

d: \(\dfrac{40}{32}-\dfrac{1}{2}=\dfrac{5}{4}-\dfrac{1}{2}=\dfrac{5-2}{4}=\dfrac{3}{4}\)

a, 1+2+4+8+16+32+...+256+512+1024

= 2⁰+2¹+2²+2³+2⁴+2⁵+...+2⁸+2⁹+2¹⁰

= 1 + 2 + 2^{2+3+4+5+...+8+9+10}

= 3+2⁵⁴

a lấy 2+8 + 4+16+......

b lấy 1+9+4+16+...

Chị Hà Anh ,hồi lớp 5 chưa học lũy thừa nên bây giờ lên lớp 6 mới hiểu dù sớm hay muộn cũng cảm ơn chị nhiều