Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
2x3 - 12x2 + 17x -2
=2x3-8x2-4x2+x+16x-2
=(2x3-8x2+x)-(4x2-16x-2)
=x(2x2-8x+1)-2(2x2-8x+1)
=(x-2)(2x2-8x+1)
\(2x^3-12x^2+17x-2\)
\(=2x^3-4x^2-8x^2+16x+x-2\)
\(=2x^2\left(x-2\right)-8x\left(x-2\right)+\left(x-2\right)\)
\(=\left(x-2\right)\left(2x^2-8x+1\right)\)
a) \(x^3-x^2-4=x^3-2x^2+x^2-4=x^2\left(x-2\right)+\left(x-2\right)\left(x+2\right)=\left(x-2\right)\left(x^2+x+2\right)\)
b) \(x^3-5x^2+8x-4=x^3-x^2-4x^2+4x+4x-4=x^2\left(x-1\right)-4x\left(x-1\right)+4\left(x-1\right)\)
\(=\left(x-1\right)\left(x^2-4x+4\right)=\left(x-1\right)\left(x-2\right)^2\)
c) \(2x^3-12x^2+17x-2=2x^3-4x^2-8x^2+16x+x-2=2x^2\left(x-2\right)-8x\left(x-2\right)+\left(x-2\right).\)
\(=\left(x-2\right)\left(2x^2-8x+1\right)\)
d) \(2x^4+x^3-22x^2+15x+36=2x^4+2x^3-x^3-x^2-21x^2-21x+36x+36.\)
\(=2x^3\left(x+1\right)-x^2\left(x+1\right)-21x\left(x+1\right)+36\left(x+1\right)\)
\(=\left(x+1\right)\left(2x^3-x^2-21x+36\right)\)
đi qua đường vào giúp cho một câu:
\(a^3+b^3+c^3-3abc\)
\(=a^3+3ab\left(a+b\right)+b^3+c^3-3abc-3ab\left(a+b\right)\)
\(=\left(a+b\right)^3+c^3-3ab\left(a+b+c\right)\)
\(=\left(a+b+c\right)\left(\left(a+b\right)^2+c\left(a+b\right)+c^2\right)-3ab\left(a+b+c\right)\)
\(\left(a+b+c\right)\left(a^2+b^2+c^2-ab-bc-ac\right)\)
==" thui thêm câu nữa mai kiểm tra 1 tiết ùi :D
\(x^2-2xy+y^2+3x-3y-10\)
\(=\left(x-y\right)^2+3\left(x-y\right)-10\)
\(=\left(x-y\right)\left(x-y+3\right)-10\)
Đặt x-y = a, có:
\(a\left(a+3\right)-10\)
\(=a^2+3a-10\)
\(=\left(a+5\right)\left(a-2\right)\)
\(=\left(x-y+5\right)\left(x-y-2\right)\)
câu trên tui viết nhầm: viết lại:
x^3+3x^2+3x+2
= (3x^2+3x)+x^3+2
= 3x(x+1)+(x+1)+(x+1)+x
= (x+1)(3x+1+1)+x
\(2x^3-12x^2+17x-2\)
\(=2x^3-4x^2-8x^2+16x+x-2\)
\(=2x^2\left(x-2\right)-8x\left(x-2\right)+\left(x-2\right)\)
\(=\left(2x^2-8x+1\right)\left(x-2\right)\)
\(2x^3-12x^2+17x-2\)
\(=2x^3-8x^2-4x^2+x+16x-2\)
\(=\left(2x^3-8x^2+x\right)-\left(4x^2-16x+2\right)\)
\(=x\left(2x^2-8x+1\right)-2\left(2x^2-8x+1\right)\)
\(=\left(2x^2-8x+1\right)\left(x-2\right)\)