bài1: tìm x:

a)\(8< 2^x< =2^9.2^5\)

b)\(27< 81^3:3^x< 243\)

c)\(\left(\frac{2}{5}\right)^x\left(\frac{5}{2}\right)^{-3}.\left(\frac{-2}{5}\right)^2\)

d)\(\left(5x+1\right)^2=\frac{36}{49}\)

e)\(\left(x-\frac{2}{9}\right)^3=\left(\frac{2}{3}\right)^6\)                                f)\(\left(8x-1\right)^{2n+1}=5^{2n+1}\)(n thuộc N)

bài 2:tìm x,y biết:

a)\(x^2+\left(y-\frac{1}{10}\right)^4=0\)

b)\(\left(\frac{1}{2}x-5\right)^{20}+\left(y^2-\frac{1}{4}\right)^{10}< =6\)

c)\(\left(x-7\right)^{x+1}-\left(x-y\right)^{x+11}=0\)

bài 3:tìm giá trị nhỏ nhất:

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

tìm Gía trị lớn nhất :\(B=-\left(\frac{4}{9}x-\frac{2}{15}\right)^6+3\)

baif4: tìm x,y:

\(x.\left(x-y\right)=\frac{1}{10}\)                                         \(\)

giúp mình với nhé

bài 2:tìm x giá trị biểu thức

a)2-\(|^{ }_{ }\)3x-\(\frac{1}{4}|\)=\(\left|-\frac{5}{4}\right|\) f)-2,5:\(\left|\frac{3}{4}x+\frac{1}{2}\right|=3\)
b)5-3.\(\left|5-2x\right|\)=-4,5 g)\(\left|2x-5\right|=\left|x=1\right|\)

c)\(\frac{3}{2}+\frac{3}{4}.\left|x-\frac{3}{4}\right|=\frac{7}{4}\)

d)\(\frac{11}{4}+\frac{3}{2}\left|4x-\frac{1}{5}\right|=\frac{7}{2}\)

e)\(\frac{21}{5}+3:\left|\frac{x}{4}-\frac{2}{3}\right|=6\) h)\(\left|\right|2x+1|-3|=\left|-5\right|\)

bài 1: Tìm x,y biết rằng:

                                  \(x+(-\frac{31}{12})^2=\left(\frac{49}{12}\right)^2-x=y^2\) 

bài 2: tìm x biết:

a.\(5^x.\left(5^3\right)^2=625\)   b.\(\left(\frac{12}{25}\right)^x=\left(\frac{5}{3}\right)^{-2}-\left(-\frac{3}{5}\right)^4\)     c.\(\left(-\frac{3}{4}\right)^{3x-1}=\frac{256}{81}\)   

d.\(172x^2-7^9:98^3=2^{-3}\)

Bài 3: Tìm x \(\varepsilon\)N biết:

a.\(8< 2^x\le2^9\times2^{-5}\)     b.\(27< 81^3:3^x< 243\)     \(\left(\frac{2}{5}\right)^x>\left(\frac{5}{2}\right)^{-3}\times\left(-\frac{2}{5}\right)^2\)c.

1.Tìm x biết

a) \(\left(\frac{2}{5}-x\right)\):\(1\frac{1}{3}+\frac{1}{2}=-4\)

b) \(\left(-3+\frac{3}{x}-\frac{1}{3}\right):\left(1+\frac{2}{5}+\frac{2}{3}\right)=-\frac{5}{4}\)

c) \(\frac{-3x}{4}.\left(\frac{1}{x}+\frac{2}{7}\right)=0\)

d) 3-\(\frac{1-\frac{1}{2}}{1+\frac{1}{x}}=2\frac{2}{3}\)

e)\(\left(2x+\frac{1}{3}\right)^2=\frac{9}{16}\)

f) \(4^x+4^{x+3}=4160\)

g) \(\left(x-2,5\right):1\frac{1}{2}=x:2\)

h) \(\left(\frac{1}{3}+x\right):\left(x+\frac{3}{4}\right)=\frac{7}{9}\)

i) 0,81:\(\frac{x}{2}=\frac{16}{x^4}:\left(-0,9\right)\)

2. Tìm x, biết:

a)\(\left(152\frac{2}{4}-148\frac{3}{8}\right):0,2=x:0,3\)

b) \(\left[\left(6\frac{3}{5}-3\frac{3}{14}\right):2,5\right]:\left(21-1,25\right)=x:5\frac{5}{6}\)