Tìm x, y biết:
A)\(\dfrac{x+1}{x-2}=\dfrac{x+2}{x-9}\)
B)\(\left[{}\begin{matrix}x\left(x+y\right)=10\\y\left(x+x\right)=6\end{matrix}\right.\)
a)
\(1\dfrac{1}{3}+2\dfrac{2}{5}-0,4-\left[{}\begin{matrix}11\\3\end{matrix}\right.:\left(\dfrac{5}{6}.\dfrac{66}{10}\right)]}\)
tìm x;y
b \(\left|x-y\right|+\left|y+\dfrac{9}{25}=0\right|\)
c \(\left(\dfrac{1}{2}x-5\right)^{20}+\left(y^2-\dfrac{1}{4}\right)^{10}=0\)
a \(\left|\dfrac{1}{2}-\dfrac{1}{3}+x\right|=\dfrac{-1}{4}-y\)
d \(\left|x\left(x^2-\dfrac{5}{4}\right)\right|=x\) \(\left(x\ge0\right)\)
e \(x^2+\left(y-\dfrac{1}{10}\right)^4=0\)
1.Tính:
\(\left(\dfrac{-2}{3}\right)\)\(\times0.75+1\dfrac{2}{3}\div\left(\dfrac{-4}{9}\right)+\left(\dfrac{-1}{2}\right)^2\)
2.Tìm x:
a)\(\dfrac{3}{4}-\left(x+\dfrac{1}{2}\right)=\dfrac{4}{5}\)
b) \(\left|x-\dfrac{2}{5}\right|+\dfrac{3}{4}=\dfrac{11}{4}\)
3.Tìm n, biết:
a) \(\dfrac{16}{2^n}=2\)
b)\(\dfrac{\left(-3\right)^n}{81}=-27\)
4. Tìm ba số x,y,z biết:
\(\dfrac{x}{2}=\dfrac{y}{3};\dfrac{y}{5}=\dfrac{z}{4}\)và x-y+z= -49
Tìm x, y, z:
a) \(\left|x+\dfrac{19}{5}\right|+\left|y+\dfrac{1890}{1975}\right|+\left|z-2005\right|=0\)
b) \(\left|x+\dfrac{3}{4}\right|+\left|y-\dfrac{1}{5}\right|+\left|x+y+z\right|\) = 0
c) \(\dfrac{16}{2^x}=1\)
d) \(\left(2x-1\right)^3=-27\)
e) \(\left(x-2\right)^2=1\)
f) \(\left(x+\dfrac{1}{2}\right)^2=\dfrac{4}{25}\)
g) \(\left(x-1\right)^2=\left(x-1\right)^6\)
Bài 1 : Tìm \(x,y,z\in Q\)
\(a)\left|x-3,5\right|+\left|4,5-y\right|=0\)
\(b)\left|x-2\right|+\left|3-y\right|=0\)
\(c)\left|x+\frac{2}{3}\right|+\left|y-\frac{3}{4}\right|+\left|z-5\right|=0\)
\(d)\left|x+\frac{13}{14}\right|+\left|x-\frac{3}{7}\right|=0\)
giúp mình với ❤❤❤
1.Tính x + y :
\(\dfrac{4^x}{2^{x+y}}\) = 8 và \(\dfrac{9^{x+y}}{3^{5y}}\) = 243
2.Tìm x, biết :
a) \(\left(x-1\right)^3\) = 343
b) \(\left(x-2\right)^4\) = 4096
c) \(\left(x-4\right)^2\) = \(\left(x-4\right)^4\)
Tìm GTLN của R=\(\frac{2018}{\left(x-2\right)^2+\left(x-y\right)^4+8}\)
tìm giá trị nhỏ nhất của các biểu thức sau:
a) \(A=\left(x^4+5\right)^2\)
b) \(B=\left(x-1\right)^2+\left(y+2\right)^2\)
c) \(C=x^2+\left|y-2\right|-5\)