Tìm x biết:
\(\sqrt{\sqrt{\sqrt{\left(x-4\right)^8}.\sqrt{\left(x+16\right)^{16}}}}=0\)
\(\left(1\right)\sqrt{x^2-9}-2\sqrt{x-3}=0\)
\(\left(2\right)\sqrt{4x+1}-\sqrt{3x-4}=1\)
\(\left(3\right)\sqrt{x^2-10x+25}=5-x\)
\(\left(4\right)\sqrt{x^2-8x+16}=x+2\)
1:
\(\Leftrightarrow\sqrt{x-3}\left(\sqrt{x+3}-2\right)=0\)
=>x-3=0 hoặc \(\sqrt{x+3}=2\)
=>x=3 hoặc x+3=4
=>x=1(loại) hoặc x=3(nhận)
2:
\(\Leftrightarrow\left(\sqrt{4x+1}-\sqrt{3x-4}\right)^2=1\)
=>\(4x-1+3x-4-2\sqrt{\left(4x+1\right)\left(3x-4\right)}=1\)
=>\(\sqrt{4\left(4x+1\right)\left(3x-4\right)}=7x-6\)
=>4(12x^2-16x+3x-4)=(7x-6)^2
=>49x^2-84x+36=48x^2-52x-16
=>-84x+36=-52x-16
=>-32x=-52
=>x=13/8
3: =>\(\sqrt{\left(x-5\right)^2}=5-x\)
=>|x-5|=5-x
=>x-5<=0
=>x<=5
4: \(\Leftrightarrow\left|x-4\right|=x+2\)
=>\(\left\{{}\begin{matrix}x>=-2\\\left(x-4\right)^2=\left(x+2\right)^2\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x>=-2\\x^2-8x+16=x^2+4x+4\end{matrix}\right.\)
=>x>=-2 và -8x+16=4x+4
=>x=1
Tìm x biết \(\sqrt{\sqrt{16}.\sqrt{\left(x-5\right)^4}}=0\)
pt <=> \(\sqrt{4.\left(x-5\right)^2}=0\)
=> \(2.lx-5l=0\)
=> \(lx-5l=0\)
=> x - 5 = 0
=> x = 5
Rút gọn biểu thức sau
A=\(\dfrac{1}{x-1}\sqrt{75\left(x-1\right)^3}\left(x>1\right)
\)
B=\(5\sqrt{4x}-3\sqrt{\dfrac{100x}{9}}-\dfrac{4}{x}\sqrt{\dfrac{x^3}{4}}\left(x>0\right)
\)
C=\(x-4+\sqrt{16-8x+x^2}\left(x>4\right)\)
Help me
a: \(A=\dfrac{1}{x-1}\cdot5\sqrt{3}\cdot\left|x-1\right|\cdot\sqrt{x-1}\)
\(=\dfrac{5\sqrt{3}}{x-1}\cdot\left(x-1\right)\cdot\sqrt{x-1}=5\sqrt{3}\cdot\sqrt{x-1}\)
b: \(B=10\sqrt{x}-3\cdot\dfrac{10\sqrt{x}}{3}-\dfrac{4}{x}\cdot\dfrac{x\sqrt{x}}{2}\)
\(=10\sqrt{x}-10\sqrt{x}-\dfrac{4\sqrt{x}}{2}=-2\sqrt{x}\)
c: \(C=x-4+\left|x-4\right|\)
=x-4+x-4
=2x-8
Giải pt: \(\left(3\sqrt{x}+\sqrt{x+8}\right)\left(4+3\sqrt{x^2+8x}\right)=16\left(x-1\right)\)
Rút gọn biểu thức N=\(\left(\dfrac{\sqrt{x}}{\sqrt{x}+4}+\dfrac{4}{\sqrt{x}-4}\right):\dfrac{\sqrt{x}+16}{\sqrt{x}+2}\) với x≥0 ; x≠16
\(=\dfrac{x-4\sqrt{x}+4\sqrt{x}+16}{x-16}\cdot\dfrac{\sqrt{x}+2}{\sqrt{x}+16}=\dfrac{\left(x+16\right)\left(\sqrt{x}+2\right)}{\left(x-16\right)\left(\sqrt{x}+16\right)}\)
Tìm điều kiện của tham số m để hệ sau đây có nghiệm
\(\left\{{}\begin{matrix}x+\sqrt{x^2+16}\le\dfrac{40}{\sqrt{x^2+16}}\\x\left(x-2\right)\left(\sqrt{x^2+y^2+3}-1\right)+\left(x^3+x+m-2\right)^2=0\end{matrix}\right.\)
\(\sqrt{4\left(x-1\right)}-\sqrt{9\left(x-1\right)}-\sqrt{16\left(x-1\right)}\)
ĐK: x \(\ge\) 1
Có:
\(=\sqrt{4}.\sqrt{x-1}-\sqrt{9}.\sqrt{x-1}-\sqrt{16}.\sqrt{x-1}\\ =2.\sqrt{x-1}-3.\sqrt{x-1}-4.\sqrt{x-1}\\ =\sqrt{x-1}\left(2-3-4\right)\\ =-5\sqrt{x-1}\)
\(=2\sqrt{x-1}-3\sqrt{x-1}-4\sqrt{x-1}\)
\(=-5\sqrt{x-1}\)
Giải phương trình:
a) \(\sqrt{\left(x-2\right)^2}=\sqrt{x-2}\)
b) \(\sqrt{x^2-1}-\sqrt{x-1}\sqrt{2x+1}=0\)
c) \(\sqrt{9\left(x-1\right)}+\sqrt{4\left(x-1\right)}-\frac{4}{5}\sqrt{25\left(x-1\right)}=1\)
d) \(\sqrt{x}+\frac{16}{\sqrt{x}}=8\)
a) \(\sqrt{\left(x-2\right)^2}=\sqrt{x-2}\)
\(\Leftrightarrow\left|x-2\right|=\sqrt{x-2}\)
\(\Leftrightarrow\left[{}\begin{matrix}x-2=\sqrt{x-2}\\-x+2=\sqrt{x-2}\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=3\\x=2\end{matrix}\right.\)
Vậy ....
Mk chỉ làm được câu a thôi mong bạn thông cảm
Điều kiện: \(2\le x\le4\)
\(\Leftrightarrow2\sqrt{x-2}-2\sqrt{2}+\sqrt{4-x}-\left(x^2-8x+16\right)=0\)
\(\Leftrightarrow\sqrt{4x-8}-2\sqrt{2}+\sqrt{4-x}-\left(4-x\right)^2=0\)
\(\Leftrightarrow\frac{-4\left(4-x\right)}{\sqrt{4x-8}+2\sqrt{2}}+\sqrt{4-x}-\left(4-x\right)^2=0\)
\(\Leftrightarrow\sqrt{4-x}\left(\frac{-4\sqrt{4-x}}{\sqrt{4x-8}+2\sqrt{2}}+1-\sqrt{4-x}^3\right)=0\)
\(\Rightarrow\sqrt{4-x}=0\Rightarrow x=4\left(tmdk\right)\) hoặc \(\left(.......\right)=0\)vô nghiệm thì phải
Vậy nghiệm là x=4