( x + 2 )( x + 4 )2( x + 8 ) = 63x2
\(\left(x+2\right)\left(x+4\right)^2\left(x+8\right)=63x^2\\ \Leftrightarrow\left(x^2+2x+8x+16\right)\left(x^2+8x+16\right)=63x^2\\ \Leftrightarrow\left(x^2+8x+16\right)^2+2x\left(x^2+8x+16\right)=63x^2\\ \Leftrightarrow\left(x^2+8x+16\right)^2+2x\left(x^2+8x+16\right)-63x^2=0\\ \Leftrightarrow\left[\left(x^2+8x+16\right)^2+2x\left(x^2+8x+16\right)+x^2\right]-64x^2=0\\ \Leftrightarrow\left(x^2+8x+16+x\right)^2-64x^2=0\\ \Leftrightarrow\left(x^2+9x+16+8x\right)\left(x^2+9x+16-8x\right)=0\\ \Leftrightarrow\left(x^2+17x+16\right)\left(x^2+x+16\right)=0\\ \Leftrightarrow\left(x^2+16x+x+16\right)\left(x^2+x+\dfrac{1}{4}+\dfrac{63}{4}\right)=0\\ \Leftrightarrow\left[\left(x^2+16x\right)+\left(x+16\right)\right]\left[\left(x^2+x+\dfrac{1}{4}\right)+\dfrac{63}{4}\right]=0\\ \Leftrightarrow\left[x\left(x+16\right)+\left(x+16\right)\right]\left[\left(x+\dfrac{1}{2}\right)^2+\dfrac{63}{4}\right]=0\)
\(\Leftrightarrow\left(x+1\right)\left(x+16\right)=0\left(\text{Vì }\left(x+\dfrac{1}{2}\right)^2+\dfrac{63}{4}e0\right)\\ \Leftrightarrow\left[{}\begin{matrix}x+1=0\\x+16=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-1\\x=-16\end{matrix}\right.\)
Vậy tập nghiệm phương trình là \(S=\left\{-1;-16\right\}\)
giải các phương trình sau:
(x2 +2x-1) (x2 + 2x -3)=3
Giải PT
(x-1)(5x+3)=(3x-8)(x-1)
a)x2-x=-2x+2
b)4x2+4x+1=x2
Giải phương trình :
a, (3x-7)2 - 4(x+1)2 = 0
b, (x+1)4 + (x+3)4 = 82
tìm x biết
\(9\left(x+2\right)-3\left(x+2\right)=0\)
\(x\left(x+5\right)+\left(x-3\right)\left(x+5\right)=0\)\(3x^2+6x=0\)
\(2\left(2x-5\right)-3x=0\)
\(\left(x-1\right)^2+x\left(5-x\right)=0\)
\(\left(2x-3\right)\left(2x+3\right)-\left(x+5\right)^2-3\left(x-1\right)\left(x+2\right)\)=0
\(\left(2x-1\right)^2-45=0\)
\(2x^2-6x=0\)
giúp vs can gap
(8x-7)(8x-5)(2x-1)(4x-1)=9
giai cac pt sau:
2x^2-5x+2=0
3x^2-7x-20=0
x^3+x^2+4=0
x^3-5x^2+8x-4=0
a) (x-3)³ + (x+1)³= 8(x-1)³
b)x⁴ - 4x² + 12x - 9 = 0)
c)x\(^5\)=x⁴ +x³ + x² + x + 2
\(\left(x+2\right)^2+\left(x-1\right)\left(x+3\right)=2\left(x-4\right)\left(x+4\right)-3\)
Giúp mk với!!!
Giải các phương trình sau:
a) \(4x^4+12x^3+5x^2-6x-15=0\)
b) \(\left(x+1\right)\left(x+2\right)\left(x+4\right)\left(x+5\right)=40\)
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