2, 

a) \(315-\left(135-x\right)=215\)

\(\Rightarrow135-x=315-215\)

\(\Rightarrow135-x=100\)

\(\Rightarrow x=135-100\)

\(\Rightarrow x=35\)

b) \(x-320:32=25\cdot16\)

\(\Rightarrow x-10=5^2\cdot4^2\)

\(\Rightarrow x-10=20^2\)

\(\Rightarrow x-10=400\)

\(\Rightarrow x=410\)

c) \(3\cdot x-2018:2=23\)

\(=3\cdot x-1009=23\)

\(\Rightarrow3\cdot x=1032\)

\(\Rightarrow x=1032:3\)

\(\Rightarrow x=344\)

d) \(280-9\cdot x-x=80\)

\(\Rightarrow280-x\cdot\left(9+1\right)=80\)

\(\Rightarrow280-10\cdot x=80\)

\(\Rightarrow10\cdot x=280-80\)

\(\Rightarrow10\cdot x=200\)

\(\Rightarrow x=20\)

e) \(38\cdot x-12\cdot x-x\cdot16=40\)

\(\Rightarrow x\cdot\left(38-12-16\right)=40\)

\(\Rightarrow x\cdot10=40\)

\(\Rightarrow x=40:10\)

\(\Rightarrow x=4\)

bài 1 cậu ko giải giúp mình dc à

a: =34x(-100)=-3400

b: =41(-76-24)=-4100

c: =-24(125-225)=2400

d: =26(-237+137)=-2600

e: =25(-63+23)=25x(-40)=-1000

(-1)+-39/13

Bài 2: 

a: =>x-35=-23

=>x=12

b: =>|x-8|=13

=>x-8=13 hoặc x-8=-13

=>x=21 hoặc x=-5

Bài 1: 

a: =42-98-42+12-12=-98

b: =10x4x3x(-25)=40x(-25)x3=-1000x3=-3000

a: Ta có: \(\left(2^{17}+17^2\right)\cdot\left(9^{15}-3^{15}\right)\cdot\left(2^4-4^2\right)\)

\(=\left(2^{17}+17^2\right)\cdot\left(9^{15}-3^{15}\right)\cdot\left(16-16\right)\)

=0

b: Ta có: \(\dfrac{8^{2017}-8^{2015}}{8^{2104}\cdot8}\)

\(=\dfrac{8^{2015}\cdot\left(8^2-1\right)}{8^{2105}}\)

\(=\dfrac{1\cdot63}{8^{90}}\)+

c: Ta có: \(\left(1^3+2^3+3^4+4^5\right)\cdot\left(1^3+2^3+3^3+4^3\right)\cdot\left(3^8-81^2\right)\)

\(=\left(1^3+2^3+3^4+4^5\right)\cdot\left(1^3+2^3+3^3+4^3\right)\cdot\left(3^8-3^8\right)\)

=0

d: Ta có: \(\left(2^8+8^3\right):\left(2^5\cdot2^3\right)\)

\(=\dfrac{2^8+2^9}{2^8}\)

=3

ra kết quả thui nhé! 

a/ 120

b/ -100

c/ 430

d/ -98

e/ A=-32

f/ B=1/10

tik nhá

\(\left(2^{17}+7^2\right).\left(9^{15}-3^{15}\right).\left(2^4-4^2\right)\)

\(=\left(2^{17}+7^2\right).\left(9^{15}-3^{15}\right).\left(16-16\right)\)

\(=\left(2^{17}+7^2\right).\left(9^{15}-3^{15}\right).0\)

\(=0\)

-------------------------------------------------

\(\left(7^{1997}-7^{1995}\right):\left(7^{1994}.7\right)\)

\(=\left[7^{1995}\left(7^2-1\right)\right]:7^{1995}\)

\(=7^{1995}.48:7^{1995}\)

\(=48\)

-------------------------------------------------

\(\left(1^2+2^3+3^4+4^5\right).\left(1^3+2^3+3^3+4^3\right).\left(3^8-81^2\right)\)

\(=\left(1^2+2^3+3^4+4^5\right).\left(1^3+2^3+3^3+4^3\right).\left(6561-6561\right)\)

\(=\left(1^2+2^3+3^4+4^5\right).\left(1^3+2^3+3^3+4^3\right).0\)

\(=0\)

-------------------------------------------------

\(\left(2^8+8^3\right):\left(2^5.2^3\right)\)

\(=\left[2^8+\left(2^3\right)^3\right]:2^8\)

\(=\left(2^8+2^9\right):2^8\)

\(=2^8.\left(1+2\right):2^8\)

\(=2^8.3:2^8\)

\(=3\)

sos

\((2^{17}+17^{2}).(9^{15}-3^{15}).(2^{4}-4^{2})\)

\(=(2^{17}+17^{2}).(9^{15}-3^{15}).(16-16)\)

\(=(2^{17}+17^{2}).(9^{15}-3^{15}).0\)

\(=0\)

\((7^{1997}-7^{1995}):(7^{1994}.7)\)

\(=(7^{1997}-7^{1995}):7^{1995}\)

\(=7^{1997}:7^{1995}-7^{1995}:7^{1995}\)

\(=7^{2}-1=49-1=48\)

\(1^{2}+2^{3}+3^{4}+4^{5}).(1^{3}+2^{3}+3^{3}+4^{3}).(3^{8}-81^{2})\)

\(=(1^{2}+2^{3}+3^{4}+4^{5}).(1^{3}+2^{3}+3^{3}+4^{3}).(6561-6561)\)

\(=(1^{2}+2^{3}+3^{4}+4^{5}).(1^{3}+2^{3}+3^{3}+4^{3}).0\)

\(=0\)

\((2^{8}+8^{3}):(2^{5}.2^{3})\)

\(=[2^{8}+(2^{3})^{3}]:2^{8}\)

\(=(2^{8}+2^{9}):2^{8}\)

\(=2^{8}:2^{8}+2^{9}:2^{8}\)

\(=1+2=3\)

b/ (-127).57+(-127).43

=(-127)(57+43)

=(-127).10

=-1270

c/ (-13).34-87.34

=34.(-13-87)

=34.(-100)

=3400

a) (-14).(-125).(+3).(-8)

= [(-14).3].[(-125).(-8)]

=     -42  . 1000

=        -42000

b) (-127).57+(-127).43

= -127.(57+43)

= -127.100

=    -12700

c) (-13).34-87.34

= 34.(-13-87)

= 34.(-100)

=  -3400

d) (-25).68+(-34).(-250)

=  - 1700 + 8500

=         6800        ( bài này không cần phải tính hợp lý )

tick nha các bạn yêu quý

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