Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Ta có: \(\left(x-2\right)^3-x\left(x-1\right)\left(x+1\right)+x\left(7x-6\right)=0\)
\(\Leftrightarrow x^3-6x^2+12x-8-x^3+x+7x^2-6x=0\)
\(\Leftrightarrow x^2+7x-8=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-8\\x=1\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=20\\x=-\dfrac{10}{7}\end{matrix}\right.\)
\(\left(x-20\right).\left(7x+10\right)=0\)
\(=>\left[{}\begin{matrix}x-20=0\\7x+10=0\end{matrix}\right.\)
\(=>\left[{}\begin{matrix}x=20\\x=-\dfrac{10}{7}\end{matrix}\right.\)
1)7x(x-5)-x(x-5)=(x-5)(7x-x)=6x(x-5)
2)x4+3x3+x+3=x3(x+3)+(x+3)=(x+3)(x3+1)=(x+3)(x+1)(x2-x+1)
3)x4+64=[(x2)2+2.x2.8+64]-16x2=(x2+8)2-(4x)2=(x2+4x+8)(x2-4x+8)
2:
a: =>(x-9)(x-1)=0
=>x=9 hoặc x=1
b: =>(x+4)(x^2-4x+16)+(x+4)(x-16)=0
=>(x+4)(x^2-4x+16+x-16)=0
=>(x+4)(x^2-3x)=0
=>x(x-3)(x+4)=0
=>x=0;x=3;x=-4
bài 2 :
a: =>(x-9)(x-1)=0
=>x=9 hoặc x=1
b: =>(x+4)(x^2-4x+16)+(x+4)(x-16)=0
=>(x+4)(x^2-4x+16+x-16)=0
=>(x+4)(x^2-3x)=0
=>x(x-3)(x+4)=0
=>x=0;x=3;x=-4
mk ghi kết quả thôi nhé, nếu từ kết quả mak k biết biến đổi thì ib cho mk
\(x^5-7x^4-x^3+43x^2-36=\left(x-6\right)\left(x-3\right)\left(x-1\right)\left(x+1\right)\left(x+2\right)\)
câu thứ 2 bạn ktra lại đề
\(x^4+2x^3-15x^2-18x+64=\left(x-2\right)\left(x^3+4x^2-7x-32\right)\)
\(x^3-x^2-4=\left(x-2\right)\left(x^2+x+2\right)\)
\(x^3-3x^2-4x+12=\left(x-3\right)\left(x-2\right)\left(x+2\right)\)
a) \(x^5-7x^4-x^3+43x^2-36\)
\(=x^3\left(x^2-1\right)-7x^2\left(x^2-1\right)+36\left(x^2-1\right)\)
\(=\left(x^2-1\right)\left(x^3-7x^2+36\right)=\left(x-1\right)\left(x+1\right)\left(x^3+2x^2-9x^2-18x+18x+36\right)\)
\(=\left(x-1\right)\left(x+1\right)\left(x+2\right)\left(x^9-9x+18\right)\)
\(=\left(x-1\right)\left(x+1\right)\left(x+2\right)\left(x-3\right)\left(x-6\right)\)
c) \(x^4+2x^3-15x^2-18x+64\)
\(=x^3\left(x-2\right)+4x^2\left(x-2\right)-7x\left(x-2\right)-32\left(x-2\right)\)
\(=\left(x-2\right)\left(x^3+4x^2-7x-32\right)\)
\(a,\Leftrightarrow\left(x+2\right)\left(x+2-x+3\right)=0\\ \Leftrightarrow5\left(x+2\right)=0\Leftrightarrow x=-2\\ b,\Leftrightarrow2x\left(x-1\right)^2=0\Leftrightarrow\left[{}\begin{matrix}x=0\\x=1\end{matrix}\right.\\ c,\Leftrightarrow\left(x-1-2x-1\right)\left(x-1+2x+1\right)=0\\ \Leftrightarrow3x\left(-x-2\right)=0\Leftrightarrow-3x\left(x+2\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\x=-2\end{matrix}\right.\)