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1. a 'havest b 'famous c de'sign
2. a 'monday b o'ccasion c 'flower
3. a e'vent b 'special c 'tourist
ĐA :1C
2B
3A
Choose the underlined words has pronouced differntly from others.
1. A. proofs B. books C. points D. days
2. A. asks B. breathes C. breaths D. hopes
3. A. sees B. breathes C. pools D. trains
4. A. tombs B. lamps C. brakes D. invites
5. A. books B. floors C. combs D. drums
6. A. cats B. tapes C. rides D. cooks
7. A. walks B. begins C. helps D. cuts
8. A. shoots B. grunds C. concentrates D. forests
9. A. helps B. laughs C. cooks D. finds
10. A. hours B. fathers C. Dreams D. thinks
1) A .studies B. leaves C. watches D. misses
2) A. history B. physics C. middle D. library
1. I beef noodle soup and my friends do ,………..
A. too B. so C. either D. neither
2. He is a famous …………….His paintings are well-known all over the world
A. poet B. singer C. painter D. musician
3. Her hobbies are …………photos and collecting toys
A. collecting B. taking C. playing D. writing
4. There isn’t ……….water in the bottle.
A. a B. an C. some D. any
5. Orange juice is my favourite ……………
A. food B. drink C. dish D. recipe
6. Turn the TV off. The show is…………………
A. exciting B. peaceful C. tiring D. boring
passive voice
1.we didn't feed our dog last night
Our dog wasn't fed last night.
2.she rides her bike to work everyday
Her bike is ridden to work everyday.
3.Do they do there homework at home?
are their homework done at home ?
4.why does Lam paint her bedroom?
why is Lam's bedroom painted ?
5.A flower is picked up in the garden by Alex
alex picks up a flower in the garden.
6.were these shoes bought by Dad?
Did Dad buy these shoes?
1. Our dog wasn't feed last night
2. Her bike is riden to work every day
3. Is their home work done at home ?
4. Why is Lam's bedroom painted ?
5. Alex pick up a flower in the garden
7. Did dad buy these shoes ?
Bài làm:
Ta có: \(\frac{a}{b}=\frac{b}{c}\) => \(b^2=ac\)
Thay vào ta được: \(\frac{a^2+b^2}{b^2+c^2}=\frac{a^2+ac}{ac+c^2}=\frac{a\left(a+c\right)}{c\left(a+c\right)}=\frac{a}{c}\)
Vậy \(\frac{a}{c}=\frac{a^2+b^2}{b^2+c^2}\)
Đặt \(\frac{a}{b}=\frac{b}{c}=k\Rightarrow\hept{\begin{cases}a=kb\\b=kc\end{cases}}\Rightarrow a=k^2c\)
\(\frac{a^2+b^2}{b^2+c^2}=\frac{\left(k^2c\right)^2+\left(kc\right)^2}{\left(kb\right)^2+c^2}=\frac{k^4b^c+k^2c^2}{k^2b^2+c^2}=\frac{k^2\left(k^2b^2+c^2\right)}{k^2b^2+c^2}=k^2=\frac{a}{c}\)( đpcm )