chứng tỏ rằng : 5 mũ 5 - 5 mũ 4 + 5 mũ 3 chia hết cho 7
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I. Choose the word in each group that has the underlined part pronounced differently from that of the rest.
1. A. watched B. looked C. fitted D. stopped
2. A. sure B. saw C. send D. sit
3. A. please B. real C. overseas D. ahead
4. A. new B. sew C. few D. knew
5. A. tool B. coop C. took D. food
6.A. talked B. visited C. rented D. fitted
7.A. help B. friend C. send D. fewer
8.A. stamp B. sew C. opposite D. bookstore
9.A. milk B. library C. dinner D. polish
10.A. pork B. go C. hold D. cold
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My father think mountain climbing (be)...is...more dangerous than skating
every year, my mother (give)...gives... me a nice doll on my birthday
my borther (not )..doesn't ... collecting stamps, he collecting glassw bottles
my sister (cook)...cooking... very much .she can cook many good foods
....Do you think.....(you/think) collecting stampscosts much money
Trả lời :
My father think mountain climbing (be)...is...more dangerous than skating
every year, my mother (give)...gives... me a nice doll on my birthday
my borther (not )..doesn't ... collecting stamps, he collecting glassw bottles
my sister (cook)...cooking... very much .she can cook many good foods
....Do you think.....(you/think) collecting stampscosts much money
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Trả lời :
I (swim)... there is a pool near my house, so I go there fours time a week to (swim)......
=> I (swim).swimming.. there is a pool near my house, so I go there fours time a week to (swim)..swim....
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Trả lời :
We (go)....to the cinema twice a month.We all love (watch).. the latest fims
=> we (go).....go.....to the cinema twice a month.We all love (watch) ........watching......... the latest fims
\(5^5-5^4+5^3=5^3\left(5^2-5+1\right)=\)
\(=5^3.21⋮7\)
Ta có: 55 - 54 + 53
= 53 (52 - 5 + 1)
= 53 . 21
Vì 21 chia hết cho 7 nên 53 . 21 chia hết cho 7
hay 55 - 54 + 53 chia hết cho 7