a: \(\left(5x-10\right):\left(100x^2+18\right)=0\)

=>5x-10=0

=>5x=10

=>x=2

b: (-300):20+5(3x-1)=25

=>-15+5(3x-1)=25

=>5(3x-1)=25+15=40

=>3x-1=8

=>3x=9

=>x=3

c: \(\left(2021x+12\right)^2\left(x+4\right)>0\)

mà \(\left(2021x+12\right)^2>0\forall x\) nguyên

nên x+4>0

=>x>-4

mà x nguyên

nên x∈{-3;-2;-1;...}

a) 407 + 24 + (-407) + (-84)

= [407 + (-407)] + 24 + (-84)

= 0 + 24 + (-84)

= 24 + (-84)

= (-60)

b) (-42) x 23 + 77 x (-42) - 200

= (-42) x (23 + 77) - 200

= (-42) x 100 - 200

= (-4200) - 200

= (-4400)

c) (-2021) + (499 + 2021) + 41

= (-2021) + 499 + 2021 + 41

= [(-2021) + 2021] + 499 + 41

= 0 + 499 + 41

= 499 + 41

= 540

d) (-202) - (34 - 202) - 66 + 50

= (-202) - 34 + 202 - 66 + 50

= [(-202) + 202] - 34 - 66 + 50

= 0 - 34 - 66 + 50

= (-34) - 66 + 50

= (-100) + 50

= (-50)

e) Bạn viết lại đề bài.

125 - 4 [ 3 - 7 . ( - 2 ) ]

= 125 - 4 [ 3 + 14 ]

= 125 - 68

= 57

18 + [ 3^3 - ( - 54 ) ]

= 18 + 81

= 99

3^8 : 3^5 + 2021^0 - ( 95 - 100 )^2

= 3^3 + 1 - 25

= 27 - 24

= 3

\(125-4\left[3-7.\left(-2\right)\right]=57\)

\(18+\left\{\left[3^3-\left(-54\right)\right]\right\}=99\)

\(3^8:3^5+2021^0-\left(95-100\right)^2=3\)

\(2021+5\left[300-\left(17-7\right)^2\right]\)
\(=2021+5\left[300-10^2\right]\)
\(=2021+5\left[300-100\right]\)
\(=2021+5\cdot200\)
\(=2021+1000=3021\)

b) 2021 + 5 [300 - (17 - 7)²]

= 2021 + 5 [ 300 - 10²]

= 2021 + 5 [ 300 - 100]

= 2021 + 5 . 200

= 2021 + 1000

= 3021

a) (300 - 150 × 2) : (1 + 2 + 3 + ... + 2021)

= (300 - 300) : (1 + 2 + 3 + ... + 2021)

= 0 : (1 + 2 + 3 + ... + 2021)

= 0

b) (312 : 13 - 24) : (26 × 7 - 8) × 2022

= (24 - 24) : (26 × 7 - 8) × 2022

= 0 : (26 × 7 - 8) × 2022

= 0 × 2022

= 0

c) (a × 10 - 90 × a : 9) × (a × 2004 + 2013)

= (10a - 90a : 9) × (a × 2004 + 2013)

= (10a - 10a) × (a × 2004 + 2013)

= 0 × (a × 2004 + 2013)

= 0

a)

\(\text{ ( 300-150x2):(1+2+3+...+2021)}\)

= \(0:(1+2+3+...+2021)\)

= \(0\)

b)

\(\text{ (312:13-24):(26x7-8)x2022}\)

 \(=0:(26x7-8)x2022\)

\(=0:174x2022\)

\(=0\)

c) 

( ax10-90xa:9)x(ax2004+2013)

= ( 10a-10a) x (ax2004+2013)

= 0 x (ax2004+2013)

= 0 

a) 3.5² + 15.2² - 26 : 2

= 3.25 + 15.4 - 13

= 75 + 60 - 13

= 135 - 13

= 122

b) 2021 + 5.[300 - (17 - 7)²]

= 2021 + 5.[300 - 10²]

= 2021 + 5.[300 - 100]

= 2021 + 5.200

= 2021 + 1000

= 3021

c) 3².5 + 2³.10 - 81

= 9.5 + 8.10 - 81

= 45 + 80 - 81

= 125 - 81

= 44

a) 3.5² + 15.2² - 26 : 2

= 3. 25 + 15 . 4 - 26 : 2

=  75  + 60 - 13

= 135 - 13

= 122

b) 2021 + 5[300 - (17 - 7)² ]

= 2021 + 5[300 - 10² ]

=2021 + 5[300 - 100]

=2021 + 5.200

=2021 + 1000

= 3021

c) 3² . 5 + 2³ . 10 - 81

= 9 . 5 + 8 . 10 - 81

= 45 + 80 - 81

= 125 - 81

= 44

a) 12 : { 400 : [500 – (125 + 25 . 7)]} 

=12 : { 400 : [500 – (125 + 175)]} 

=12 : [ 400 : [500 – 300)]

=12 : (400:200)

=12:2=6

b) 5 . 2² – 18 : 3

=5.4-6

=20-6=14

c) 18 : 3 + 182 + 3.(51 : 17)

=5+182+3.3

=187+9=196

d) 25 . 8 – 12.5 + 170 : 17 – 8

=200-60+10-8

=142

e) 2.5²+ 3: 71⁰ – 54: 3³ 

=2.25+3:1-54:27

=50+3-2

=51

f) 189 + 73 + 211 + 127

=(189+211)+(73+127)
=400+200=600

g) 375 : {32 – [ 4 + (5. 32– 42)]} – 14 )

 =375 : {32 – [ 4 + (160– 42)]} – 14 )

 =375 : [32 – ( 4 + 118) – 14 ]

=375:(32-122-14)

=375:-104

=-375/104

h) (5²⁰²² + 5²⁰²¹) : 5²⁰²¹

=(5²⁰²²:5²⁰²¹)+(5²⁰²¹:5²⁰²¹)

=5+1=6

a: =-36-329-71+136-2021

=100-400-2021

=-300-2021

=-2321

\(E=2\sqrt{3}+3\sqrt{3^3}-\sqrt{100.3}\\ =2\sqrt{3}+9\sqrt{3}-10\sqrt{3}\\ =\left(2+9-10\right)\sqrt{3}=\sqrt{3}\)

\(F=\sqrt{3^2.2}+4\sqrt{18}=\sqrt{18}+4\sqrt{18}=\left(1+4\right)\sqrt{18}=5\sqrt{18}\)

\(G=2\sqrt{3}-4\sqrt{3^3}+5\sqrt{4^2.3}=2\sqrt{3}-12\sqrt{3}+20\sqrt{3}=\left(2-12+20\right)\sqrt{3}=10\sqrt{3}\)

\(H=\left(3\sqrt{25.2}-5\sqrt{9.2}+3\sqrt{2^3}\right)\sqrt{2}\\ =\left(15\sqrt{2}-15\sqrt{2}+6\sqrt{2}\right)\sqrt{2}\\ =6\sqrt{2}.\sqrt{2}=6\)