ĐKXĐ: \(x^2-x\ge0\)
\(3\sqrt{x^2-x}=\sqrt{54}\)
\(\Rightarrow9\left(x^2-x\right)=54\)
\(\Rightarrow x^2-x-6=0\Rightarrow\left[{}\begin{matrix}x=3\\x=-2\end{matrix}\right.\) (thỏa mãn)
Tìm x , y , z thỏa mãn :
\(\sqrt{\left(x-3\sqrt{5}\right)^2}+\sqrt{\left(y+3\sqrt{5}\right)^2}\) + I x + y + z I = 0
1. Tìm x thuộc Z, biết:
\(9^{x-1}=\dfrac{1}{9}\)
2. Tìm x biết:
\(\dfrac{1}{3}:\sqrt{7-3x^2}=\dfrac{2}{15}\)
3. Tìm các số x,y,z thỏa mãn:
\(\sqrt{\left(x-\sqrt{2}\right)^2}+\sqrt{\left(y+\sqrt{2}\right)^2}+\left|x+y+z\right|=0\)
Rút gọn:
\(A=\left[\dfrac{2\left(x+y\right)}{\sqrt{x^3}-2\sqrt{2y^3}}-\dfrac{\sqrt{x}}{x+\sqrt{2xy}+2y}\right].\left[\dfrac{x\sqrt{x}+2\sqrt{2y^3}}{2y+\sqrt{2xy}}-\sqrt{x}\right]\)
Tìm x biết
a) \(x-3\sqrt{x}=0\)
b)\(5\sqrt{x}-x=0\)
1. Tìm x, biết:
a) \(9^{x-1}=\frac{1}{9}\)
b) \(\frac{1}{3}:\sqrt{7-3x^2}=\frac{2}{15}\)
2. Tìm các số x,y,z thỏa mãn:
\(\sqrt{\left(x-\sqrt{2}\right)^2}+\sqrt{\left(y+\sqrt{2}\right)^2}+\left|x+y+z\right|=0\)
Tìm x biết :
1. \(\sqrt{x-1}=2\)
2. \(\sqrt{3-x}=1\)
3. \(\left|x-1\right|+\left|x^2-1\right|=0\)
4. \(\left|2x-3\right|-\left|x-1\right|=0\)
Help me!! Thanks for helping !!
a. \(\sqrt{\left(\sqrt{9-1}\right)^2}\)
b. \(\sqrt{x+3=5}\)
c. \(\sqrt{3x-2}-7=0\)
d. \(\sqrt{2x}=8\)
Bài 1Trong các số sau đây số nào bằng \(\dfrac{3}{5}\)
a,\(\sqrt{\dfrac{3^2}{5^2}}\)
b,\(\dfrac{\sqrt{3^2}+\sqrt{42^2}}{\sqrt{5^2}+\sqrt{70^2}}\)
c,\(\dfrac{\sqrt{3^2}-\sqrt{8^2}}{\sqrt{5^2}-\sqrt{8^2}}\)
Bài 2
a, \(x=\sqrt{3}+\sqrt{6}\)
\(y=2\sqrt{3}\)
b,\(x=\sqrt{3}+\sqrt{6}\)
\(y=\sqrt{2}+\sqrt{7}\)
c,\(x=-\dfrac{1}{2}\sqrt{\dfrac{1}{3}}\)
\(y=-\dfrac{1}{3}\sqrt{\dfrac{1}{2}}\)
Bài 3
\(a,\sqrt{x}-1=4\)
\(b,\sqrt{\left(x-1\right)^4}=16\)
Tìm x biết:
a, \(\sqrt{x-1}\) = 3 b,\(x^2\) - 64 = 0
c,\(x^2\) + 16 = 25 d,|\(\sqrt{x}-3\)| + 3 = 9
