Vì \(\left|2x-27\right|^{2011}\ge0;\left(3y+10\right)^{2012}\ge0\) mà

\(\left|2x-27\right|^{2017}+\left(3y+10\right)^{2012}=0\) nên ta có:

\(\Rightarrow\left[{}\begin{matrix}2x-27=0\\3y+10=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}2x=27\\3y=-10\end{matrix}\right.\Rightarrow}\left[{}\begin{matrix}x=\dfrac{27}{2}\\y=\dfrac{-10}{3}\end{matrix}\right.\)

Vậy \(x=\dfrac{27}{2};y=\dfrac{-10}{3}\)

\(\dfrac{3}{4}-\dfrac{4}{9}.\dfrac{27}{16}=\dfrac{3}{4}\left(1-\dfrac{4}{9}.\dfrac{9}{4}\right)=\dfrac{3}{4}.\left(1-1\right)=0\)

\(\left|x\right|+5=8\)

\(\left|x\right|=3\)

\(\Rightarrow x=3\) hoặc \(x=-3\)

Vậy \(x\in\left\{-3;3\right\}\)

a,\(2\left|3x-1\right|-1=6\)

\(2\left|3x-1\right|=7\)

\(\left|3x-1\right|=3,5\)

\(\Rightarrow\left\{{}\begin{matrix}3x-1=3,5\\3x-1=-3,5\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}3x=4,5\\3x=-2,5\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=1,5\\x=\dfrac{-5}{6}\end{matrix}\right.\)Vậy \(x\in\left\{\dfrac{-5}{6};1,5\right\}\)

1. They....that bridge when i was there last year, they haven't finish it

A. are building

B. built

C. was building

D. were building

2. They .... only 25 new students into the department in 1994

A. admit

B. were admit

C. admitted

D. have admitted

3. He... to the theater three times this month

A. was

B. is

C. will be

D. has been

4. He ... the experiment when the lights went out

A. was making

B. made

C. makes

D. will make

5. Think carefully. I am sure you ... his name

A. remember

B. remembered

C. will remember

D. shall remember

6. Last night we were watching TV when the power.....

A. failed

B. was failing

C. had faided

D. failing

7. He had a bad fall while he ... his roof

A. was repairing

B. repaired

C. repairs

D. will repair

8. Mary will finish the work when her father...

A. returns

B. will return

C. returned

D. was returning

9. My brother .... in Vietnam and he.... home once a year

A. work/returns

B. work/ return

C. works/returns

D. works/return

10. The test..... in ten minutes' time. You must hurry

A. began

B. begin

C. will begin

D. has begun

11. She kept looking at me while i .... to the teacher

A. were talking

B. was talking

C. talked

D. talking

12. His first article.... in Le Monde in October 1928

A. appears

B. appear

C. appeared

D. didn't appeared

13. '' Mother, I ... my medicine. Can i go out now ?''

A. have taken

B. had taken

C. has taken

D. will have taken

14. Don't.... all the time. people will not be fooled by you twice

A. lying

B. lie

C. lied

D. lies

15. The teacher....our class two tests so far

A. have given

B. gave

C. gives

D. has given

16. Doctors and scientists .... recently the benefit of fish in the diet

A. have shown

B. show

C.are showing

D. had shown

Ta có: \(\dfrac{x^4-5x^2+4}{x^4-10x^2+9}\)\(=\dfrac{x^4-x^2-4x^2+4}{x^4-x^2-9x^2+9}=\dfrac{x^2\left(x^2-1\right)-4\left(x^2-1\right)}{x^2\left(x^2-1\right)-9\left(x^2-1\right)}\)

\(=\dfrac{\left(x^2-1\right)\left(x^2-4\right)}{\left(x^2-1\right)\left(x^2-9\right)}\)\(=\dfrac{\left(x-2\right)\left(x+2\right)}{\left(x-3\right)\left(x+3\right)}\).

a,\(5^3\left[\left(-7\right)+\left(-2\right)^3\right]+4\)

\(=125.\left[\left(-7\right)+\left(-8\right)\right]+4\)

\(=125.\left(-15\right)+4\)

\(=-1875+4=-1871.\)

b,\(47\left(45-15\right)-47\left(45+15\right)\)

\(=47\left(45-15-45-15\right)\)

\(=47.\left(-30\right)=-1410.\)

c,\(71.64-32.\left(-7\right)-32.\left(-11\right)\)

\(=32.\left(142+7+11\right)\)

\(=32.160=5120.\)

Theo đề: \(a+\dfrac{1}{a}=2\Rightarrow\left(a+\dfrac{1}{a}\right)^2=4\)

\(\Rightarrow a^2+2a.\dfrac{1}{a}+\dfrac{1}{a^2}=4\)

\(\Rightarrow a^2+2+\dfrac{1}{a^2}=4\Rightarrow a^2+\dfrac{1}{a^2}=2\)

Vậy \(a^2+\dfrac{1}{a^2}=2\)

Ta có: \(f\left(0\right)=a.0^2+b.0+c=1\Rightarrow c=1.\)

Lại có: \(f\left(1\right)=a.1^2+b.1+1=2\Rightarrow a+b=1.\)

\(f\left(2\right)=2^2.a+2b+1=2\)

\(\Rightarrow4a+2b=a+b\)

\(\Rightarrow3a+b=0\)\(\Rightarrow6a+2b=0\)\(\Rightarrow2a=-1\Rightarrow a=-0,5\)

\(\Rightarrow b=1,5\)

Vậy: \(a=-0,5\)

\(b=1,5\)

\(c=1\)

\(\)

1. He's a new pupil in our class

2. Where is your address in Ha Noi?

3. Now I live with my grandparentsin Ha Noi

4. I live in Flat 16 on the second floor of Ha Noi Tower

5. I lived in a village in the mountain

6. What's your village like ? It's small and quiet

7. The family lives on the third floor of CM Tower.

8. His flat is far from the city centre

9. His new school is near his house

10. Their flat is big and modern