Tìm đkxd: a) $\sqrt{3x-1}$
b) $\frac{5x-1}{\sqrt{2-x}}$
c) $\frac{\sqrt{x-5}}{x^2+5x+6}$

$2^x$ = 32
3^x+¹ - 1 = 0
1/3 + 2/3 : x = 1/4
3/5 - 2/5 x = 1/3
(2x + 1 )³ - 1/8 =0
( 1 - 4/3)²
(2/3 - 1/2 )³
4⁷/4⁸ ; 3⁵/3³
8⁷. 6⁵/8⁸. 6⁴

Rút gọn ps
c)$3\times \frac{5}{8}\times 24$
d) $8\times 5-8\times \frac{2}{16}$
e) 2.14/7.8
f)11.4-11/2-13
g)17.5-17/3-20
h)49+7.49/49

tìm x
a) 1+3+5+...+x=25 ( x là stn lẻ)
b ) $\left(\frac{1}{1\times 2}+\frac{1}{2\times 4}+...+\frac{1}{28\times 30}\right)\times 114-0,2\times \left(x-1\right)=10$

viết cách khác của các tập hợp
E={x thuộc N|10≤x<15}
K= {x thuộc N*|x ≤ 3

Tìm x : x × (x-1) + 2x - 2=0
b,Cmr:$n^3-3n^2-n+3$ chia hết cho 48 ( n thuộc N,n lẻ)

Phân tích đa thức thành nhân tử
1) $x^2$ + 6x + 9

2) 1 + 4$x^2$ + 4xy

3) $-4a^4+12ab-9b^4$
4) $16a^2+9b^2-36ab$

5) $16-8y+y^2$

6) 144a ^ 2 - 24a * b ^ 2 + b ^ 4

7) - 25x ^ 2 * y ^ 2 - 20x * y ^ 2 - 4y ^ 2

8) 9x ^ 2 - 12xy + y ^ 2

9) b ^ 2 - b + 1/4

10) - 49x ^ 2 - 36y ^ 2 + 84xy

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Without your help, I can't finish my work.
->If you don't________________
Work too fast, you will make so many mistakes.
->If________________________
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Tính
a,$\sqrt{49}\times \sqrt{144}+\sqrt{256}÷\sqrt{64}$
b, $72÷\sqrt{2^2}\times 36\times 3^2-\sqrt{225}$

Tính bằng cách hợp lí
a) $\frac{3}{4\times 7}+\frac{3}{7\times 10}+\frac{3}{10\times 13}+...+\frac{3}{64\times 67}$
b) $A=\frac{12}{4\times 7}+\frac{12}{7\times 10}+...+\frac{12}{61\times 64}+\frac{11}{64\times 67}$

$$\begin{gathered} \mathit{A}\mathit{ }\mathit{=}\mathit{ }\mathit{2}\mathit{ }\mathit{+}\mathit{ }{\mathit{2}}^{\mathit{2}}\mathit{+}\mathit{ }{\mathit{2}}^{\mathit{2}}\mathit{+}\mathit{ }{\mathit{2}}^{\mathit{3}}\mathit{+}\mathit{ }\mathit{.}\mathit{.}\mathit{.}\mathit{ }\mathit{+}{\mathit{2}}^{\mathit{10}} \\ \mathit{C}\mathit{h}\mathit{ứ}\mathit{n}\mathit{g}\mathit{ }\mathit{m}\mathit{i}\mathit{n}\mathit{h}\mathit{ }\mathit{A}\mathit{ }\mathit{c}\mathit{h}\mathit{i}\mathit{a}\mathit{ }\mathit{đ}\mathit{c}\mathit{ }\mathit{c}\mathit{h}\mathit{o}\mathit{ }\mathit{6}\mathit{ }\mathit{(}\mathit{ }\mathit{g}\mathit{i}\mathit{ú}\mathit{p}\mathit{ }\mathit{e}\mathit{ }\mathit{n}\mathit{h}\mathit{a}\mathit{ }\mathit{<}\mathit{3} \end{gathered}$$