\(a,\frac{3}{4}-x=1\) \(b,x+4=\frac{1}{5}\) \(c,x-\frac{1}{5}=2\)

\(d,x+\frac{5}{3}=\frac{1}{81}\) \(e,x-\frac{10}{3}=\frac{7}{15}.\frac{3}{5}\) \(g,x+\frac{3}{22}=\frac{27}{121}.\frac{11}{9}\)

\(h,1-x=\frac{49}{65}.\frac{5}{7}\) \(i,\frac{8}{23}.\frac{46}{24}-x=\frac{1}{3}\) \(k,\frac{62}{7}.x=\frac{29}{9}:\frac{3}{56}\)

Câu 6 : Tìm giá trị lớn nhất của biểu thức 

a ) K = \(\frac{1}{\left(x-\frac{3}{2}\right)^2+\frac{1}{4}}\)                       

b ) G = -7 . | 5x - 2 | - 11                             

c ) Q = \(\frac{1}{\left(x-3\right)^2+8}\)

d ) B = \(4-\frac{\left(2x+1\right)^2}{x^2+1}\)                                               

e ) D = \(-5.\left(x+\frac{2}{5}\right)^2+\frac{9}{5}\)

g ) A = \(\frac{3}{\left(x+\frac{1}{2}\right)^2+\frac{3}{4}}\)

h ) P =\(\frac{1}{\left(x-2\right)^2+5}\)

i ) C = \(\frac{1}{\left(y-\frac{3}{2}\right)^2+\frac{5}{4}}\)

k ) E = \(3-\frac{1}{-\left(x-\frac{3}{2}\right)^2-\frac{11}{4}}\)

So sánh hai phân số sau:

a)\(\frac{7}{15}và\frac{4}{9}\)

b)\(\frac{2001}{2002}và\frac{2000}{2001}\)

c)\(\left(\frac{1}{80}\right)^7và\left(\frac{1}{243}\right)^6\)

d)\(\left(\frac{3}{8}\right)^5và\left(\frac{5}{243}\right)^3\)

e) A=\(\frac{2011}{2012}+\frac{2012}{2013}\)Và  B=  \(\frac{2011+2012}{2012+2013}\)

f)  \(C=\frac{20^{10}+1}{20^{10}-1}VàD=\frac{20^{10}-1}{20^{10}-3}\)

g) G =\(\frac{10^{100}+2}{10^{100}-1}\)Và   H = \(\frac{10^8}{10^8-3}\)

h)  E = \(\frac{98^{99}+1}{98^{89}+1}\) Và   F =\(\frac{98^{98}+1}{98^{88}+1}\)

Bài 5 : Chững minh rẳng :
a) S= \(\frac{3}{10}+\frac{3}{11}+\frac{3}{12}+\frac{3}{13}+\frac{3}{14}\) CMR :1< S <2
b) \(\frac{1}{4^2}+\frac{1}{6^2}+\frac{1}{8^2}+\frac{1}{10^2}+...+\frac{1}{\left(2n\right)^2}< \frac{1}{4}\)
c) \(\frac{3}{4}+\frac{8}{9}+\frac{15}{16}+...+\frac{2499}{2500}>48\)
d) \(\frac{1}{5}+\frac{1}{13}+\frac{1}{14}+\frac{1}{15}+\frac{1}{61}+\frac{1}{62}+\frac{1}{63}< \frac{1}{2}\)
Bài :So sánh phân số sau:
a)\(\frac{1985.1987-1}{1980+1985.1986}và1\)
b) A= \(\frac{13^{15}+1}{13^{16}+1}\)và B = \(\frac{13^{16}+1}{13^{17}+1}\)
c)\(\frac{18}{53}và\frac{26}{79}\)
d)\(\frac{5}{8}và\frac{14}{17}\)
e)\(\frac{1}{5^{199}}và\frac{1}{3^{300}}\)
g)\(\frac{1}{3^{17}}và\frac{1}{5^{10}}\)
h) \(\frac{18}{109}và\frac{5}{30}\)

Bài 1: So sánh các ps sau: 

a)\(\frac{1}{2};\frac{1}{3};\frac{2}{3}\)

b)\(\frac{4}{9};-\frac{1}{2};\frac{3}{7}\)

c)\(\frac{3}{124};\frac{1}{41};\frac{5}{207};\frac{2}{83}\)

d)\(\frac{134}{43};\frac{55}{21};\frac{74}{19};\frac{116}{37}\)

e)\(\frac{16}{9};\frac{24}{13}\)

g)\(\frac{-2525}{2929};\frac{-217}{245}\)

h)\(\frac{27}{82};\frac{26}{75}\)

i)\(\frac{-49}{75};\frac{64}{-95}\)

1.  A=\(\frac{3}{x-1}\)
2.  \(B=\frac{3}{x-3}\)
3.  \(C=\frac{x-5}{x}\)
4.  \(D=\frac{x-3}{2x}\)
5.  \(E=\frac{-3}{x-1}\)
6.   \(F=\frac{-4}{2x-1}\)
7.  \(G=\frac{3x+7}{x-1}\)
8. \(H=\frac{4x-1}{3-x}\)
9. \(I=\frac{x-2}{x+3}\)
10.  \(K=\frac{2x+1}{x-3}\)
11. \(M=\frac{x^2+1}{x+1}\)