Bài 3:

a)3.5²-16:2²=71

b)15.141+59.15=15(141+59)=3000

c)2³.17-2³.14=2³(17-14)=8.3=24

(câu b hình như thiếu dấu "+"?)

a) 71

b) 24

c) 3000

Tick cho mình.

a)3.5²-16:2²

= 3. 25 - 16 :4

= 75 - 4

= 71

b)15.141+59.15

= 15.(141+59)

= 15. 200

= 3000

c)2³.17-2³.14

= 2³ .(17-14)

= 8 . 3

= 24

`a, 3.5^2 -16:2^2`

`= 3. 25 - 16:4`

`= 75 - 4`

`=71`

_____

`b, 15.141 +59 . 15`

`= 15. (141+59)`

`=15. 200`

`=3000`

______

`c, 2^3 . 17 - 2^3 .14`

`= 2^3 . (17-14)`

`= 8 . 3`

`=24`

a: =3^7*3^15*3^12=3^34

b: =(36:18)^5=2^5=32

c: =5^7-5^5=5^5(5^2-1)=5^5*24=75000

d: =5^12:5^8=5^4=625

a: =3*25-16:4

=75-4=71

b: =15(141+59)

=15*200=3000

c: =2^3(17-14)=2^3*3=24

b: \(=15\left(141+19\right)=15\cdot160=24000\)

c: \(=2^3\cdot\left(17-14\right)=8\cdot3=24\)

a,  3 . 5 2 - 16 : 2 2 = 3.25  - 16:4 = 75 - 4 = 71

b, 15.141 + 59.15 = 15.(141+59) = 15.200 = 3000

c,  2 3 . 17 - 2 3 . 14 = 8.17 - 8.14 = 8.(17 - 14) = 8.3 = 24

d, 20 - 30 - 5 - 1 2 = 20 - 30 - 4 2 = 20 - (30 - 16) = 20 - 14 = 6

15.141+59.15=2115+885=3000

20-[30-(5-1²)]=20-[30-(5-1)]=20-[30-4)]=20-26=.....chỗ này đề bài sai nha bn

20-[30-(5-1^2)]=20-[30-(5-1)^2]=20-[30-4^2]=20-[30-16]=20-14=6

Bài 3: 

a: Ta có: 60-3(x-2)=51

\(\Leftrightarrow x-2=3\)

hay x=5

b: Ta có: \(4x-20=25:2^2\)

\(\Leftrightarrow4x=\dfrac{25}{4}+20=\dfrac{105}{4}\)

hay \(x=\dfrac{105}{16}\)

c: Ta có: \(8\cdot6+288:\left(x-3\right)^2=50\)

\(\Leftrightarrow288:\left(x-3\right)^2=50-48=2\)

\(\Leftrightarrow\left(x-3\right)^2=144\)

\(\Leftrightarrow\left[{}\begin{matrix}x-3=12\\x-3=-12\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=15\\x=-9\end{matrix}\right.\)

a: 3*5^2-16:2^2

=3*25-16:4

=75-4=71

b: =2^3(17-14)

=8*3

=24

c: =15(141+59)

=15*200

=3000

d: =17(85+15)-200

=1700-200

=1500

f: =3+2^5

=3+32

=35

g: =42(39-37):42

=39-37

=2

\(3\cdot5^2-16:2^2=3\cdot25-16:4=75-4=71\)

3.5² - 16 : 2²

= 3 . 25 - 16 : 4

= 75 - 4 = 71

\(=2^3\cdot3+3\cdot5^2-8=24-8+75=91\)

=8(17-14)+3.25-16:2

=24+75-8

=91