17-15=?
(Free tick)
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Gọi \(S=\frac{15}{15\cdot16}+\frac{15}{16\cdot17}+..+\frac{15}{19\cdot20}\)
\(\Leftrightarrow S=1-\frac{15}{16}+\frac{15}{16}-\frac{15}{17}+...+\frac{15}{19}-\frac{15}{20}\)
\(\Leftrightarrow S=1-\frac{15}{20}=\frac{1}{4}<\frac{1}{3}\)
Vậy S< \(\frac{1}{3}\)
--------------------Good luck------------------------
complete the sentences . use the present simple or future simple form of the verbs
14.what (you/do).......do you do....... in your free time ?
15......Do...........you (water)......water........the tree every morning?
16.mary often(go).....goes.....to school by bike
17..........Will......your father (play)...play...... football next summer ?
18.Mai (love).......loves.......dolls but she (not continue).....doesn't continue........
19.I hope the weather (be) will be fine tonight
20. my mother sometimes (buy)...buys...... fruit at this super market
21.who(look).....looks....... after the garden when you are away ?
15. She failed the driving test because she didn’t follow the guidance of the driving ………… instructor….…..( instruct )
16. In Malaysia ………education………………….is free and compulsory for children between age of 6 and 16. ( educate )
17. Is Christmas a ……………international………………… holiday . ( nation )
18. Coffee is one of the most ……………important……………agricultural products exported from Viet Nam. ( importance )
19. We’ve impressed by the …………friendliness……………..of your town’s people. ( friend)
20. They enjoy the …………friendly………………………….atmosphere in the meeting. ( friend)
21. The …………friendship.………………they made at school will last through their life.. ( friend)
22. ……………beautiful…….parks and lakes in Hanoi attract tourists. ( Beauty)
23. The little girl is dancing ………………beautifully………………… ( beauty)
24. English is the …………official……………..language in Singapore. ( office)
25. Malaysia has …………tropical…………………………………climate. (tropic)
26. Most……………instructionw………………are written in English. (instruct)
27. They go to church every Sunday. They’re……………religious…………………. (religion)
28. Our………………national…………..flag is red and yellow. ( nation)
17-15=2
:((((
17 - 15 = 2.