103,37 - 38,79 - 3,37

= ( 103,37 - 3,37 ) - 38,79

=          100             - 38 ,79

=                       61,21

Bài 1:So sánh Avà B biết rằng:

A=\(\frac{10^{15}+1}{10^{16}+1};\) B=\(\frac{10^{16}+1}{10^{17}+1}\)

A=\(\frac{3}{8^3}+\frac{7}{8^4}\); B=\(\frac{7}{8^3}+\frac{3}{8^4}\)

A=\(\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+.......+\frac{1}{19}+\frac{1}{20};\) B=\(\frac{1}{2}\)

Bài 2:Dạng tính tổng đặc biệt:

\(A=\frac{1}{1\cdot2}+\frac{1}{2\cdot3}+\frac{1}{3\cdot4}+.....+\frac{1}{99\cdot100}\)

\(B=\frac{2}{1\cdot3}+\frac{2}{3\cdot5}+\frac{2}{5\cdot7}+.....+\frac{2}{99\cdot101}\)

\(C=\frac{3^2}{10}+\frac{3^2}{40}+\frac{3^2}{88}+......+\frac{3^2}{340}\)

\(D=\frac{1}{3}+\frac{1}{3^2}+\frac{1}{3^3}+......+\frac{1}{3^8}\)

\(E=\left(1-\frac{1}{2}\right)\cdot\left(1-\frac{1}{3}\right)\cdot\left(1-\frac{1}{4}\right).......\left(1-\frac{1}{99}\right)\)

Bài 3:Dạng chứng minh:

\(A=1+\frac{1}{2}+\frac{1}{3}+......+\frac{1}{99}.\)Chứng minh rằng A chia hết cho 100

A=\(\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+...+\frac{1}{70}\).Chứng minh rằng A>\(\frac{4}{3}\)

ẼII.Circle to the best answer

1.A.diswasher B.tenis C.washing machine D.wireless TV

2.A.reduce B.reuse C.recycle D.bedroom

3......................does she live?

A.How B.Where C.What D.When

4.Hoa and I usually...................up at 7.00

A.get B.to get C.gets D.getting

5.They are going to..................Ha Noi

A.visites B.visits C.visiting D.visit

6.He isn't tall.He is.........

A.shorter B.the shortest C.short D.shorting

7.Thu and Vui........soccer at the moment

A.are playing B.is playing C.play D.am playing

8.What about......to school by bike

A.go B.going C.to go D.goes

9.My father ....................Da Latin 2010

A.go B.goes C.visited D.been

10.If the weather.....................good.I.............camping with classmates

A.is/go B.is/will go C.will be /go D.will be/will go

11.My sister....... home for school yet

A.didn't leave B.don't leave C.hasn't left D.isn't leaving

12.Amstterdam is one of the...................cities in the world

A.peacefulest B.peacefuler C.most peaceful D.more peaceful

13.The people here are .......................

A.friendly B.delicious C.polluter D.long

14.He like playing table tennis,................he can't play it

A.and B.but C.so D.or

15 They couldn't go on a picnic...................the weather was bad

A.because B.when C.but D.or

16. My house is .........................to the supermarket

A.to the left B.behind C.near D.next

17......................does she go to school?

A.How B.who C.what D.which

18.Mai.............up at 6.00

A.get B.to get C.gets D.getting

19.He is going to .....................Ha Long Bay for a week

A.satyes B.stay C.staying D.stays

20.They aren't fat .They are..................

A.thiner B.the thinest C.to thin D.thin

21.He......................soccer at the moment

A.are playing B.is playing C.play D.am playing

22.Let's .........................to school by bike

A.go B.going C.to go D.goes

23.My father didn't ........................Da Lat in 2010

A.went B.visit C.visited D.been

24.If the weather................bad,I..............at home with my classmates

A.is/will stay B.is/will C.will be /go D.will be /will go

25.They ..................home for school yet

A.haven't left B.don'tleave C.hasn't left D.isn't leaving

ai giúp mình với trước 7:30,mình tặng like nha !!!!!!