1 If we continue polluting the air, the environment will be affected seriously

2 If we don't stop damaging birds' homes, there will be fewer birds left

3 If we continue polluting the water, there will be more disease in people and animals

4 If we keep polluting the land, the soil will not be safe enough for us to grow food in

5 If we use public transportation when we need, there will be less air pollution

12 Daniel signs up for a clean-up campaign so that he can join in it

13 People in my neighborhood clean the park up so that their children will have a nice place to play

14 Almost all the students in my school plant trees so that they can have much fresher air

e: \(\dfrac{x^2+3x+9}{x^3+4x^2+4x}\cdot\dfrac{x^2+2x}{x^3-27x}\)

\(=\dfrac{x^2+3x+9}{x\left(x^2+4x+4\right)}\cdot\dfrac{x\left(x+2\right)}{x\left(x^2-27\right)}\)

\(=\dfrac{x^2+3x+9}{\left(x+2\right)^2}\cdot\dfrac{x+2}{x\left(x^2-27\right)}\)

\(=\dfrac{\left(x^2+3x+9\right)}{\left(x+2\right)\cdot x\left(x^2-27\right)}\)

f: \(\dfrac{2x^2+4xy+2y^2}{5x-5y}\cdot\dfrac{15x-15y}{2x^3+2y^3}\)

\(=\dfrac{2\left(x^2+2xy+y^2\right)}{5\left(x-y\right)}\cdot\dfrac{15\left(x-y\right)}{2\left(x^3+y^3\right)}\)

\(=\dfrac{\left(x+y\right)^2}{1}\cdot\dfrac{3}{\left(x+y\right)\left(x^2-xy+y^2\right)}\)

\(=\dfrac{3\left(x+y\right)}{x^2-xy+y^2}\)

g: \(\dfrac{x^3-4x}{x^2-7x+12}\cdot\dfrac{x-4}{x^2-2x}\)

\(=\dfrac{x\left(x^2-4\right)}{\left(x-3\right)\left(x-4\right)}\cdot\dfrac{x-4}{x\left(x-2\right)}\)

\(=\dfrac{x^2-4}{\left(x-3\right)\left(x-2\right)}=\dfrac{\left(x-2\right)\left(x+2\right)}{\left(x-3\right)\left(x-2\right)}=\dfrac{x+2}{x-3}\)

\(x:y:z=\dfrac{4}{7}:\dfrac{5}{8}:\dfrac{9}{10}=160:175:252\)

Giúp e vs e đg rất gấp ạ

\(4x^4+1\)

\(=4x^4+4x^2+1-4x^2\)

\(=\left(2x^2+1\right)^2-\left(2x\right)^2\)

\(=\left(2x^2+1+2x\right)\left(2x^2+1-2x\right)\)

\(4x^4+1=4x^4+4x^2+1-4x^2=\left(2x^2+1\right)^2-\left(2x\right)^2\)

\(=\left(2x^2-2x+1\right)\left(2x^2+2x+1\right)\)

9. A
10. D
5. A
6. B
7. D
8. B
 

9 A

10 D

:)

1.B dynamite
2.B disappear
3.B refreshment
4.C disappointed
5.C division
6.C disappointment
7.B congratulate
8.D inedible
9.C congratulation
10.A oceanic

--thodagbun--

1 A

3 C

4 C

5 A

6 B

10 A

1 If I were you I would recycle these plastic carrier bags

2 The pilots suddenly struck, so all flights had to be cancelled

3 The polluted environment causes the death of birds and plants

4 The contaminated food leads to people's poor health

a) \(f\left(x\right)+g\left(x\right)-h\left(x\right)\)

\(=\left(2x^5-4^4x^4+3x^3-x^2+5x-1\right)+\left(-x^5+2x^4-3x^3-x^2-2x+7\right)-\left(x^5-2x^4-2x^2-x-3\right)\)

\(=2x^5-4x^4+3x^3-x^2+5x-1-x^5+2x^4-3x^3-x^2-2x+7-x^5+2x^4+2x^2+x+3\)\(=\left(2x^5-x^5-x^5\right)-\left(4x^4-2x^4-2x^4\right)+\left(3x^3-3x^3\right)-\left(x^2+x^2-2x^2\right)+\left(5x-2x+x\right)-\left(1-7-3\right)\)

\(=0-0+0-0+4x-9\)

\(=4x-9\)

`a,`

`f(x)+g(x)-h(x)=(2x^5-4x^4+3x^3-x^2+5x-1)+(-x^5+2x^4-3x^3-x^2-2x+7)-(x^5-2x^4-2x^2-x-3)`

`= 2x^5-4x^4+3x^3-x^2+5x-1+ -x^5+2x^4-3x^3-x^2-2x+7-x^5+2x^4+2x^2+x+3`

`= (2x^5-x^5-x^5)-(4x^4-2x^4-2x^4)+(3x^3-3x^3)-(x^2-2x^2)-(2x-x)+(-1+7+3)`

`= 0-0+0-(-x^2)-x+10 = x^2-x+9`

cho mình làm lại ;-;

`a,`

`f(x)+g(x)-h(x)=(2x^5-4x^4+3x^3-x^2+5x-1)+(-x^5+2x^4-3x^3-x^2-2x+7)-(x^5-2x^4-2x^2-x-3)`

`= 2x^5-4x^4+3x^3-x^2+5x-1+ -x^5+2x^4-3x^3-x^2-2x+7-x^5+2x^4+2x^2+x+3`

`= (2x^5-x^5-x^5)-(4x^4-2x^4-2x^4)+(3x^3-3x^3)-(x^2+x^2-2x^2)+(5x-2x+x)+(-1+7+3)`

`= 0-0+0-0+4x+9 = 4x+9 `