Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\left(2x-3\right)^2-9.\left(4x^2-9\right)^2=0\)
\(\Leftrightarrow\left(2x-3\right)^2-\left(3.\left(4x^2-9\right)\right)^2=0\)
\(\Leftrightarrow\left(2x-3-3.\left(4x^2-9\right)\right).\left(2x-3+3.\left(4x^2-9\right)\right)=0\)
\(\Leftrightarrow\left(2x-3-3.\left(2x-3\right).\left(2x+3\right)\right).\left(2x-3+3.\left(2x-3\right).\left(2x+3\right)\right)=0\)
\(\Leftrightarrow\left(\left(2x-3\right).\left(1-3.\left(2x+3\right)\right)\right).\left(\left(2x-3\right).\left(1+3.\left(2x+3\right)\right)\right)=0\)
\(\Leftrightarrow\left(\left(2x-3\right).\left(-8-6x\right)\right).\left(\left(2x-3\right).\left(10+6x\right)\right)=0\)
\(\Leftrightarrow\left(2x-3\right)^2.\left(-8-6x\right).\left(10+6x\right)=0\)
Tiếp tục giải ra thôi, dễ quá đi mất
\(\)
\(\left(x+3\right)\left(x^2-3x+9\right)-x\left(x^2-9\right)=27\\ x.x^2-x.3x+x.9-x.x^2+x.9=27\\ x^3-3x^2+9x-x^3+9x=27\\ 3x^2+18x=27\\ 21x^2=27\\ x^2=\dfrac{9}{7}\\ \Rightarrow x=\sqrt{\dfrac{9}{7}}\)
\(\dfrac{x}{x^2-9}+\dfrac{2}{x^2+6x+9}=\dfrac{x\left(x+3\right)+2\left(x-3\right)}{\left(x-3\right)\left(x+3\right)^2}\\ =\dfrac{x^2+5x-6}{\left(x-3\right)\left(x+3\right)^2}=\dfrac{\left(x-1\right)\left(x+6\right)}{\left(x-3\right)\left(x+3\right)^2}\)
\(\Rightarrow x^2-9=0\Rightarrow\left(x-3\right)\left(x+3\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=3\\x=-3\end{matrix}\right.\)
\(25x^2-9=0\\ \Leftrightarrow\left(5x-3\right)\left(5x+3\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}5x=3\\5x=-3\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{3}{5}\\x=\dfrac{3}{5}\end{matrix}\right.\)
=>(5x-3)(5x+3)=0
=>5x-3=0 hoặc 5x+3=0
=>x=3/5 hoặc x=-3/5
$x(x^2-3)=9+x^3\\\Leftrightarrow x^3-3x=9+x^3\\\Leftrightarrow x^3-3x-x^3=9\\\Leftrightarrow -3x=9\\\Leftrightarrow x=-3$
Vậy giá trị của $x$ cần tìm là $x=-3$
( 2 x – 3 ) 2 – 4 x 2 + 9 = 0 ⇔ ( 2 x – 3 ) 2 – ( 4 x 2 – 9 ) = 0 ⇔ ( 2 x – 3 ) 2 – ( ( 2 x ) 2 – 3 2 ) = 0 ⇔ ( 2 x – 3 ) 2 – ( 2 x – 3 ) ( 2 x + 3 ) = 0
ó (2x – 3)(2x – 3 – 2x – 3) = 0
ó (2x – 3)(-6) = 0
ó 2x – 3 = 0
ó x = 3 2
Đáp án cần chọn là: C
\(4x^2-9=3x\left(2x-3\right)\)
\(\Rightarrow\left(2x-3\right)\left(2x+3\right)-3x\left(2x-3\right)=0\)
\(\Rightarrow\left(2x-3\right)\left(-x+3\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{3}{2}\\x=3\end{matrix}\right.\)
\(\Rightarrow\left(2x-3\right)\left(2x+3\right)-3x\left(2x-3\right)=0\\ \Rightarrow\left(2x-3\right)\left(2x+3-3x\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{3}{2}\\x=3\end{matrix}\right.\)
Ta có \(9\cdot\cdot\cdot564.6=1092877\cdot\)
mà \(6.4=24\)
\(\Rightarrow\)\(\cdot=4\)