\(\dfrac{12^4.\left(-10^2\right)}{3^4.4^5.5^2}=\dfrac{3^4.2^8.2^2.\left(-5^2\right)}{3^4.2^{10}.5^2}=\dfrac{3^4.2^{10}.\left(-5^2\right)}{3^4.2^{10}.5^2}=-1\)
1) \(\dfrac{-5}{\dfrac{12}{\left|\dfrac{2}{3}x+\dfrac{1}{2}\right|}}\)= \(\dfrac{\dfrac{-4}{9}}{\dfrac{8}{15}}\)
2) \(\dfrac{\left|3x-5\right|}{-3}\)= \(\dfrac{\dfrac{-5}{6}}{\dfrac{4}{9}}\)
tính
a, \(\left(\dfrac{5}{3}-\dfrac{1}{2}\right):\left(\dfrac{3}{4}-\dfrac{5}{2}\right)\)
b,\(\left(\dfrac{1}{6}+\dfrac{1}{3}\right)^2\cdot\left(1+\dfrac{2}{3}-\dfrac{5}{4}\right)\)
c, \(\dfrac{4^{30}\cdot3^{43}}{2^{57}\cdot27^{15}}\)
1.Tìm x trong các tỉ lệ thức sau:
a,\(16:x^2+x:\left(-4\right)\)
b,\(x:0,27=3:x\)
c,\(0,81:\dfrac{x}{2}=\dfrac{16}{x^4}:\left(-0,9\right)\)
d,\(\dfrac{x-1}{x+2}=\dfrac{x-2}{x+3}\)
e,\(\left(x+15\right):x=\dfrac{4}{3}\)
f,\(\left(x-20\right):\left(x-10\right)=\left(x+40\right):\left(x+70\right)\)
2.Tìm số nguyên x mà khi cùng thêm vào tử và mẫu của phân số \(\dfrac{26}{39}\) ta được phân số mới có giá trị bằng \(\dfrac{6}{7}\)
3. Cho \(\dfrac{a+5}{a-5}=\dfrac{b+6}{b-6}\) (với a≠5, b≠6). Chứng minh rằng \(\dfrac{a}{b}=\dfrac{5}{6}\)
\(\left|2x+3\right|+\left|2x-1\right|=\dfrac{8}{3.\left(x+1\right)^2+2}\)\(\sqrt{ }\)\(\left|2x+3\right|+\left|2x-1\right|\)=\(\dfrac{8}{3.\left(x+1\right)^2+2}\)
tìm x,y thuộc Z biết:
a, \(\left(x+4\right)\left(y+3\right)=3\)
b,\(\left(x+2\right)\left(y-3\right)=-3\)
c,\(\dfrac{x+1}{2}=\dfrac{1}{y}\)
d, \(\dfrac{x-7}{-1}=\dfrac{13}{2-y}\)
Tìm x , x biết :
a) / x - z / - / - \(\dfrac{3}{7}\) / = 10
b) / \(\left(x+\dfrac{1}{2}\right)\) / 2 x - \(\dfrac{3}{4}\) / / = 2x - \(\dfrac{3}{4}\)
c) / x / \(x^2\) + \(\dfrac{3}{4}\) // = 2x - \(\dfrac{3}{4}\)
Tìm x, biết:
\(\dfrac{1+2.a}{8}=\dfrac{2+5.a}{12}=\dfrac{1+a}{4.x}\left(a\in Q,x\ne0\right).\)
tỉ lệ thức
( x- 6 ) : ( -1,5) = -6 : ( x- 6 )
\(1\dfrac{2}{3}:\left(x-4\right)=5\dfrac{1}{6}:\left(x+1\right)\)
Tìm \(x\) trong các tỉ lệ thức sau :
a) \(3,8:\left(2x\right)=\dfrac{1}{4}:2\dfrac{2}{3}\)
b) \(\left(0,25x\right):3=\dfrac{5}{6}:0,125\)
c) \(0,01:2,5=\left(0,75x\right):0,75\)
d) \(1\dfrac{1}{3}:0,8=\dfrac{2}{3}:\left(0,1x\right)\)
