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1. His health is getting ...................... and ...................... .

A.good / good

B.better / better

C.bad / bad

D.well/ well

2.The more paper we save, ................... preserved.

A.more is wood pulp

B.the more wood pulp is

C.wood pulp is

D.the much wood pulp is

3.The more polluted air we breathe, ................... we get.

A.the more weaker

B.the more weak

C.the weaker

D.weaker more

4. The more we study, the ....................... we are.

A.more good

B.better

C.better than

D.good

5. The more I tried my best to help her, ......................... shebecame.

A.less lazy

B.the lazier

C.the more lazy

D.lazier

6. “What’s your thought of her presence here?” “The longer she stays, .................I dislike her.”

A.the most

B.the very more

C.much more

D.the more

7. The weather becomes ..........................

A.colder with colder

B.colder and colder

C.colder and more cold

D.more and more cold

8. The more he slept, ........................ irritable he became.

A.the most

B.the very more

C.much more

D.the more

9. ................. he worked, the more money he earned

A.The more hard

B.The hard

C.The harder

D.The hardest

10. ................ I get to know Jim, the more I like him.

A.For more

B.More

C.The more

D.The most

11. The competition makes the price of goods .........................

A.most cheap and cheap

B.cheaper and cheaper

C.more cheap and more cheap

D.cheaper and more cheaper

12. That factory is producing ................... pollution.

A. more and more

B. better and better

C. less and least

D. more and less

13. The ……..….. I read about history, the ………….. it makes me realize how relevant history is for us today.

A. more / better

B. better / better

C. more / more

D. better / more

14. The less we study, the .................... we are.

A. worse

B. bad

C. well

D. good

15. ................. the match was, the more spectators it attracted.

A. The most interesting

B. The best interesting

C. The more interesting

D. The interesting

16. The more running water you use, .........................

A. your bill will be higher

B. will be higher your bill

C. the higher your bill will be

D. the highest your bill will be

1. that house looks so big

2. i can see a nice picture behind you

3. they will move to a new apartment next week

Giải:

Đặt $\frac{a}{b}=\frac{c}{d}=k$ $\Rightarrow$ $\{\begin{array}{c}a=bk\\ c=dk\end{array}$

Thay vào vế trái ta có:

$\frac{2a+3b}{2a-3b}=\frac{2bk+3b}{2bk-3b}=\frac{b\left(2k+3\right)}{b\left(2k-3\right)}=\frac{2k+3}{2k-3}$

Thay vào vế phải ta có:

$\frac{2c+3d}{2c-3d}=\frac{2dk+3d}{2dk-3d}=\frac{d\left(2k+3\right)}{d\left(2k-3\right)}=\frac{2k+3}{2k-3}$

đkxđ: x≠0;x≠5

thu gọn A

A=x3+2x2+2x2−50+50−5x2x(x+5)

A=x−12

để A = 1

thì x=3

để A=-3

x=-5

Điều kiện xác định của phương trình : $x\ge 5$

PT : $\sqrt{x+1}=x-5\iff \left(x+1\right)-\sqrt{x+1}-6=0$

Đặt $t=\sqrt{x+1},t\ge 0$

pt trở thành $t^2-t-6=0\iff \left(t-3\right)\left(t+2\right)=0$

$\iff [\begin{array}{c}t=3\left(\text{nhận}\right)\\ t=-2\left(\text{loại}\right)\end{array}$

Với t = 3 , suy ra x = 8

Vậy phương trình có nghiệm x = 8

a) $x\ne 0;x\ne 1$

b)

Khi $x=0$, phân thức không được xác định (mẫu = 0) hay không thỏa mãn điều kiện

Khi $x=3$

$A=\frac{2x-1}{x^2-x}=\frac{2\cdot 3-1}{3^2-3}=\frac{5}{6}$

a) Đê C có nghĩa => $\{\begin{array}{c}2x-2\ne 0\\ 2-2x^2\ne 0\end{array}$

=> $\{\begin{array}{c}x-1\ne 0\\ \left(x-1\right)\left(x+1\right)\ne 0\end{array}$

=> $x\ne \pm 1$

b) Ta có: C = $\frac{x}{2x-2}+\frac{x^2+1}{2-2x^2}$ => C = $\frac{x\left(x+1\right)}{2\left(x-1\right)\left(x+1\right)}-\frac{x^2+1}{2\left(x-1\right)\left(x+1\right)}$

=> C = $\frac{x^2+x-x^2-1}{2\left(x-1\right)\left(x+1\right)}$ = $\frac{1}{}$

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