a: \(x^3-9x^2+6x+16\)

\(=x^3-8x^2-x^2+8x-2x+16\)

\(=x^2\left(x-8\right)-x\left(x-8\right)-2\left(x-8\right)\)

\(=\left(x-8\right)\left(x^2-x-2\right)\)

\(=\left(x-8\right)\left(x-2\right)\left(x+1\right)\)

b: \(x^3-x^2-x-2\)

\(=x^3-2x^2+x^2-2x+x-2\)

\(=x^2\left(x-2\right)+x\left(x-2\right)+\left(x-2\right)\)

\(=\left(x-2\right)\cdot\left(x^2+x+1\right)\)

c: \(x^3+x^2-x+2\)

\(=x^3+2x^2-x^2-2x+x+2\)

\(=x^2\left(x+2\right)-x\left(x+2\right)+\left(x+2\right)\)

\(=\left(x+2\right)\left(x^2-x+1\right)\)

d: \(x^3-6x^2-x+30\)

\(=x^3+2x^2-8x^2-16x+15x+30\)

\(=x^2\left(x+2\right)-8x\left(x+2\right)+15\left(x+2\right)\)

\(=\left(x+2\right)\left(x^2-8x+15\right)\)

\(=\left(x+2\right)\left(x-3\right)\left(x-5\right)\)

e: Sửa đề: \(x^3-7x-6\)

\(=x^3-x-6x-6\)

\(=x\left(x^2-1\right)-6\left(x+1\right)\)

\(=x\left(x-1\right)\left(x+1\right)-6\left(x+1\right)\)

\(=\left(x+1\right)\left(x^2-x-6\right)\)

\(=\left(x+1\right)\left(x-3\right)\left(x+2\right)\)

f: \(27x^3-27x^2+18x-4\)

\(=27x^3-9x^2-18x^2+6x+12x-4\)

\(=9x^2\left(3x-1\right)-6x\left(3x-1\right)+4\left(3x-1\right)\)

\(=\left(3x-1\right)\left(9x^2-6x+4\right)\)

g: \(2x^3-x^2+5x+3\)

\(=2x^3+x^2-2x^2-x+6x+3\)

\(=x^2\left(2x+1\right)-x\left(2x+1\right)+3\left(2x+1\right)\)

\(=\left(2x+1\right)\left(x^2-x+3\right)\)

h: \(\left(x^2-3\right)^2+16\)

\(=x^4-6x^2+9+16\)

\(=x^4-6x^2+25\)

\(=x^4+10x^2+25-16x^2\)

\(=\left(x^2+5\right)^2-\left(4x\right)^2\)

\(=\left(x^2+5+4x\right)\left(x^2+5-4x\right)\)

\(=x^2-6x+9-2=\left(x-3\right)^2-2=\left(x-3-\sqrt{2}\right)\left(x-3+\sqrt{2}\right)\)

\(=\left(x^2-6x+9\right)-2=\left(x-3\right)^2-\sqrt{2^2}=\left(x-3-\sqrt{2}\right)\left(x-3+\sqrt{2}\right)\)

=x2−6x+9−2=(x−3)2−2=(x−3−√2)(x−3+√2)

      \(x^4+6x^3+7x^2-6x+1\)

\(=x^4+6x^3+9x^2-2x^2-6x+1\)

\(=\left(x^2\right)^2+2.x^2.3x+\left(3x\right)^2-2\left(x^2+3x\right)+1\)

\(=\left(x^2+3x\right)^2-2\left(x^2+3x\right).1+1^2\)

\(=\left(x^2+3x-1\right)^2\)

Chúc bạn học tốt.

\(x^4+6x^3+7x^2-6x+1\)

\(=x^4+6x^3+9x^2-2x^2-6x+1\)

\(=x^2\left(x+3\right)^2-2\left(x^2+3x\right)+1\)

\(=\left(x^2+3x\right)^2-2\left(x^2+3x\right)+1=\left(x^2+3x-1\right)^2\)

https://olm.vn/hoi-dap/tim-kiem?q=Cho+%CE%94ABC+vu%C3%B4ng+t%E1%BA%A1i+A+c%C3%B3+AB+%3E+AC,+M+l%C3%A0+%C4%91i%E1%BB%83m+tu%E1%BB%B3+%C3%BD+tr%C3%AAn+BC.+Qua+M+k%E1%BA%BB+Mx+vu%C3%B4ng+g%C3%B3c+v%E1%BB%9Bi+BC+v%C3%A0+c%E1%BA%AFt+AB+t%E1%BA%A1i+I+c%E1%BA%AFt+CA+t%E1%BA%A1i+D.a.+Ch%E1%BB%A9ng+minh+%CE%94ABC+%C4%91%E1%BB%93ng+d%E1%BA%A1ng+v%E1%BB%9Bi+%CE%94MDCb.+Ch%E1%BB%A9ng+minh:+BI.BA+=+BM.BCc.+Cho+g%C3%B3c+ACB+=+60o+v%C3%A0+S%CE%94CDB+=+60+cm2.+T%C3%ADnh+S%CE%94CMAGi%C3%BAp+m%C3%ACnh+c%C3%A2u+c+v%E1%BB%9Bi&id=573451

x^4+6x^3+7x^2–6x+1

=x^4+(6x^3–2x^2)+(9x^2–6x+1)

= x^4+2x^2(3x–1)+(3x–1)^2

=(x^2+3x–1)^2

TƯƠNG TỰ CÁC BÀI TRONG NÂNG CAO PHÁT TRIỂN 8

\(x^4-6x^3+7x^2-6x+1\)

\(=x^4+x^2+1-6x^3+6x^2-6x\)

\(=\left(x^2+1\right)^2-x^2-6x\left(x^2-x+1\right)\)

\(=\left(x^2+x+1\right)\left(x^2-x+1\right)-6x\left(x^2-x+1\right)\)

\(=\left(x^2-x+1\right)\left(x^2+x+1-6x\right)\)

\(=\left(x^2-x+1\right)\left(x^2-5x+1\right)\)

= x⁴ - x³ + x² - 5x³ + 5x² - 5x + x² - x +1  = x² ( x² - x +1 ) - 5x ( x² - x +1 ) + x² - x +1 = ( x² - x +1 ) ( x² - 5x + 1 )

mk ko biết

A=x^4+6x^3+7x^2–6x+1=x^4+(6x^3–2x^2)+(9x^2–6x+1)
= x^4+2x^2(3x–1)+(3x–1)^2 =(x^2+3x–1)^2

chỉnh lại tí

Đặt P(x)=x⁴+6x³+7x²- 6x+1

Đặt y=x²-1

=>y²=x⁴-2x²+1

P(x)=x⁴-2x²+1+6x³-6x+9x²

  =(x²-1)²+6x(x²-1)+9x²

Q(y)=y²+6xy+9x²

=(y+3x)²

P(x)=(x²-1+3x)²

Đặt P(x)=x⁴+6x³+7x²- 6x+1

Đặt y=x²-1

=>y²=x⁴-2x²+1

P(x)=x⁴-2x²+1+6x³-6x+9x²

  =(x²-1)²+6x(x²-1)+9x²

Q(y)=y²+6xy+9x²

=(y+3x)²

P(x)=(x²-1+3x)²

\(=x^2\left(x-6\right)-24\left(x-6\right)=\left(x^2-24\right)\left(x-6\right)\)

\(x^3-6x^2-24x+144=\left(x^3-6x^2\right)-\left(24x-144\right)=x^2\left(x-6\right)-24\left(x-6\right)=\left(x-6\right)\left(x^2-24\right)\)