Phân tích đa thứ thành nhân tử:
a) a2+b2+2ab+2a+2b+1
b) a3-3a+3b-b3
c) x2+2x-15
d) a4+6a2b+9b2-1
Phân tích đa thức thành nhân tử:
a) 5ab-45a3b
b) 3a-6ab+5-10b
c) a2-7ab-2a+14b
d) 4a2-8b+4a-8ab
e) a2-5a+15b-9b2
a,\(5ab-45a^3b\)
=\(5ab\left(1-9a^2\right)\)
=\(5ab\left(1-3a\right)\left(1+3a\right)\)
b,\(3a-6ab+5-10b\)
=\(\left(3a-6ab\right)+\left(5-10b\right)\)
=\(3a\left(1-2b\right)+5\left(1-2b\right)\)
=\(\left(1-2b\right)\left(3a+5\right)\)
c,\(a^2-7ab-2a+14b\)
=\(\left(a^2-7ab\right)-\left(2a-14b\right)\)
=\(a\left(a-7b\right)-2\left(a-7b\right)\)
=\(\left(a-7b\right)\left(a-2\right)\)
d,\(4a^2-8b+4a-8ab\)
=\(\left(4a^2-8ab\right)+\left(4a-8b\right)\)
=\(4a\left(a-2b\right)+4\left(a-2b\right)\)
=\(\left(a-2b\right)\left(4a+4\right)\)
=\(4\left(a-2b\right)\left(a+1\right)\)
e,\(a^2-5a+15b-9b^2\)
=\(\left(a^2-9b^2\right)-\left(5a-15b\right)\)
=\(\left(a-3b\right)\left(a+3b\right)-5\left(a-3b\right)\)
=\(\left(a-3b\right)\left(a+3b-5\right)\)
Phân tích đa thức thành nhân tử:
a) 3x2y - 6xy2 + 3y2
b) a2 - b2 + 2a + 2b
c) x2 + 6x + 9 - y2
d) x2 - 9x + 20
a)3y(x2 -2xy+y)
b)=(a+b)(a-b)+2(a+b)
=(a+b)(a-b+2)
Bài 1: Phân tích đa thức thành nhân tử:
a) x2 + xy –x – y
b) a2 – b2 + 8a + 16
TK
a) x2 + xy –x – y = x(x + y) – (x + y) = (x + y)(x -1 ).
b) a2 – b2 + 8a + 16 = (a2 + 8a + 16) – b2 = (a + 4)2 – b2
= (a + 4 – b)(a + 4 + b).
Phân tích các đa thức sau thành nhân tử
a,3a-3b+a^2-2ab+b^2
b,a^2-2ab+b^2-2a-2b+1
a) \(3a-3b+a^2-2ab+b^2\)
\(=3\left(a-b\right)+\left(a-b\right)^2\)
\(=\left(a-b\right)\left(a-b+3\right)\)
a)
3.(a-b) +2.(a-b ) =5 .(a-b )
câu b làm tương tự nha nhóm a^2 -2ab +b^2 vào 1nhoms và làm như câu a
mình làm nhầm
a) \(\left(a-b\right).\left(a-b+3\right)\)
Phân tích các đa thức sau thành nhân tử:
a) x2 - 9 - x2 (x2 - 9) d) x2 + 5x + 6 h) a2 + b2 + 2a – 2b – 2ab
b) x2(x-y) + y2(y-x) e) 3x2 – 4x – 4 i) (x + 1)2 – 2(x + 1)(y – 3) + (y – 3)2
c) x3+27+(x+3)(x-9) g) x4 + 64y4 k) x2(x + 1) – 2x(x + 1) + x + 1
Mình đang cần gấp ạ
a: \(x^2-9-x^2\left(x^2-9\right)\)
\(=\left(x^2-9\right)-x^2\left(x^2-9\right)\)
\(=\left(x^2-9\right)\left(1-x^2\right)\)
\(=\left(1-x\right)\left(1+x\right)\left(x-3\right)\left(x+3\right)\)
b: \(x^2\left(x-y\right)+y^2\left(y-x\right)\)
\(=x^2\left(x-y\right)-y^2\left(x-y\right)\)
\(=\left(x-y\right)\left(x^2-y^2\right)\)
\(=\left(x-y\right)\left(x-y\right)\left(x+y\right)=\left(x-y\right)^2\cdot\left(x+y\right)\)
c: \(x^3+27+\left(x+3\right)\left(x-9\right)\)
\(=\left(x+3\right)\left(x^2-3x+9\right)+\left(x+3\right)\left(x-9\right)\)
\(=\left(x+3\right)\left(x^2-3x+9+x-9\right)\)
\(=\left(x+3\right)\left(x^2-2x\right)=x\left(x-2\right)\left(x+3\right)\)
d: \(x^2+5x+6\)
\(=x^2+2x+3x+6\)
\(=x\left(x+2\right)+3\left(x+2\right)=\left(x+2\right)\left(x+3\right)\)
e: \(3x^2-4x-4\)
\(=3x^2-6x+2x-4\)
\(=3x\left(x-2\right)+2\left(x-2\right)\)
\(=\left(x-2\right)\left(3x+2\right)\)
g: \(x^4+64y^4\)
\(=x^4+16x^2y^2+64y^4-16x^2y^2\)
\(=\left(x^2+8y^2\right)^2-\left(4xy\right)^2\)
\(=\left(x^2+8y^2-4xy\right)\left(x^2+8y^2+4xy\right)\)
h: \(a^2+b^2+2a-2b-2ab\)
\(=a^2-2ab+b^2+2a-2b\)
\(=\left(a-b\right)^2+2\left(a-b\right)=\left(a-b\right)\left(a-b+2\right)\)
i: \(\left(x+1\right)^2-2\left(x+1\right)\left(y-3\right)+\left(y-3\right)^2\)
\(=\left(x+1-y+3\right)^2\)
\(=\left(x-y+4\right)^2\)
k: \(x^2\left(x+1\right)-2x\left(x+1\right)+\left(x+1\right)\)
\(=\left(x+1\right)\left(x^2-2x+1\right)\)
\(=\left(x+1\right)\left(x-1\right)^2\)
Bài 1: Phân tích đa thức thành nhân tử:
a) x2y+xy+x+1
b) x2-(a+b)x+ab
c) ax2+ay-bx2-by
d) ax-2x-a2+2a
e) 2x2+4ax+x+2a
f) x3+ax2+x+a
g) x4+2x3-4x-4
a) x2y+xy+x+1= (x2y+xy)+(x+1)=xy(x+10+(x+1)=(x+1)(xy+1)
b) x2-(a+b)x+ab=x2-ax-bx+ab=(x2-ax)-(bx-ab)=x(x-a)-b(x-a)=(x-a)(x-b)
c) ax2+ay-bx2-by=(ax2+ay)-(bx2+by)=a(x2+y)-b(x2+y)=(a-b)(x2+y)
d) ax-2x-a2+2a=(ax-2x)-(a2-2a)=x(a-2)-a(a-2)=(a-2)(x-a)
e) 2x2+4ax+x+2a=(2x2+4ax)+(x+2a)=2x(x+2a)+(x+2a)=(x+2a)(2x+1)
f) x3+ax2+x+a=(x3+ax2)+(x+a)=x2(x+a)+(x+a)=(x2+1)(x+a)
g: Ta có: \(x^4+2x^3-4x-4\)
\(=\left(x^2-2\right)\left(x^2+2\right)-2x\left(x^2-2\right)\)
\(=\left(x^2-2\right)\cdot\left(x^2+2x+2\right)\)
Phân tích đa thức thành nhân tử:
a) (a2 + b2- 5)2- 4(ab + 2)2
b) bc(b + c) + ca(c - a) - ab(a + b);
a: Ta có: \(\left(a^2+b^2-5\right)^2-4\left(ab+2\right)^2\)
\(=\left(a^2+b^2-5-2ab-4\right)\left(a^2+b^2-5+2ab+4\right)\)
\(=\left[\left(a-b\right)^2-9\right]\cdot\left[\left(a+b\right)^2-1\right]\)
\(=\left(a-b-3\right)\left(a-b+3\right)\left(a+b-1\right)\left(a+b+1\right)\)
1.Phân tích các đa thức sau thành nhân tử:
a) a4 - 9a3 + a2 - 9a
b) 3x2 + 5y - 3xy + (-5x)
c) 2xy + 3z + 6y +xz
d) x2 - (a+b)x + ab
a) \(=a\left(a^3-9a^2+a-9\right)=a\left[a^2\left(a-9\right)+\left(a-9\right)\right]\)
\(=a\left(a-9\right)\left(a^2+1\right)\)
b) \(=3x\left(x-y\right)-5\left(x-y\right)=\left(x-y\right)\left(3x-5\right)\)
c) \(=x\left(2y+z\right)+3\left(2y+z\right)=\left(2y+z\right)\left(x+3\right)\)
d) \(=x^2-ax-bx+ab=x\left(x-a\right)-b\left(x-a\right)\)
\(=\left(x-a\right)\left(x-b\right)\)
a) = a(a³-9a²+a-9)
b) =3x²+5y-3xy-5x
= (3x²-5x)+(5y-3xy)
=x(3x-5)+y(5-3x)
=x(3x-5)-y(3x-5)
=(3x-5)(x-y)
c)2xy +3z+6y+xz
=(2xy+6y)+(3z+xz)
=2y(x+3)+z(3+x)
=(x+3)(2y-z)
a) \(a^4-9a^3+a^2-9a=a\left(a^3-9a^2+a-9\right)=a\left[\left(a^3-9a^2\right)+\left(a-9\right)\right]=a\left(a^2+1\right)\left(a-9\right)\)
Phân tích đa thức thành nhân tử:
a) 4abc-8ab2c
b)x2(2a-1)+x(1-2a)
c) 9a4(a-2)+a2(a-2)
d) (a-4)(2a-1)-8a+4
a, \(4abc-8ab^2c=4abc\left(1-2b\right)\)
b, \(x^2\left(2a-1\right)+x\left(1-2a\right)=x^2\left(2a-1\right)-x\left(2a-1\right)\)
\(=x\left(x-1\right)\left(2a-1\right)\)
c, \(9a^4\left(a-2\right)+a^2\left(a-2\right)=a^2\left(9a^2+1\right)\left(a-2\right)\)
d, \(\left(a-4\right)\left(2a-1\right)-8a+4=\left(a-4\right)\left(2a-1\right)-4\left(2a-1\right)\)
\(=\left(a-8\right)\left(2a-1\right)\)
a) `4abc-8ab^2c=4abc(1-2b)`
b) `x^2 (2a-1)+x(1-2a) = x^2 (2a-1) -x(2a-1) = (2a-1)(x^2-x)=x(2a-1)(x-1)`
c) `9a^4 (a-2) +a^2 (a-2) = (a-2)(9a^4+a^2)=a^2 (a-2)(9a^2+1)`
d) `(a-4)(2a-1)-8a+4=(a-4)(2a-1)-4(2a-1)=(2a-1)(a-8)`
cho a,b là 2 số thực phân biệt thỏa mãn a2-3a=b2-3b=1. Tính giá trị của:
a+b ; a2+b2 ; a3+b3 ; a4+b4 ; a5+b5 ; a6+b6