Phân tích thành nhân tử :
a) \(x^2+5x-6\)
b) \(5x^2+5xy-x-y\)
c) \(7x-6x^2-2\)
\(x^2 +5x-6\)
\(5x^2 +5xy-x-y\)
\(7x-6x^2 -2\)
Phân tích thành nhân tử
\(x^2+5x-6\\ =x^2-x+6x-6\\ =x\left(x-1\right)+6\left(x-1\right)\\ =\left(x+6\right)\left(x-1\right)\\ ---\\ 5x^2+5xy-x-y\\ =x\left(5x-1\right)+y\left(5x-1\right)\\ =\left(5x-1\right)\left(x+y\right)\\ ----\\ 7x-6x^2-2\\ =-6x^2+3x+4x-2\\ =-3x\left(2x-1\right)+2\left(2x-1\right)\\ =\left(2-3x\right)\left(2x-1\right)\)
\(x^2+5x-6=\left(x-1\right)\left(x+6\right)\\ 5x^2+5xy-x-y=\left(5x-1\right)\left(x+y\right)\\ 7x-6x^2-2=\left(3x-2\right)\left(2x-1\right)\)
Phân tích thành nhân tử:
x^2 + 5x - 6
5x^2 + 5xy - x - y
7x - 6x^2 - 2
\(x^2+5x-6=x^2-x+6x-6=x\left(x-1\right)+6\left(x-1\right)=\left(x+6\right)\left(x-1\right)\)
\(5x^2+5xy-x-y=5x\left(x+y\right)-\left(x+y\right)=\left(5x-1\right)\left(x+y\right)\)
\(7x-6x^2-2=3x-6x^2+4x-2=3x\left(1-2x\right)-2\left(1-2x\right)=\left(3x-2\right)\left(1-2x\right)\)
\(a,x^2+5x-6=x^2-x+6x-6\)
\(=x\left(x-1\right)+6\left(x-1\right)=\left(x-1\right)\left(x+6\right)\)
\(b,5x^2+5xy-x-y=5x\left(x+y\right)-\left(x+y\right)\)
\(=\left(x+y\right)\left(5x-1\right)\)
\(c,7x-6x^2-2=-6x^2+3x+4x-2\)
\(=-3x\left(2x-1\right)+2\left(2x-1\right)=\left(2x-1\right)\left(2-3x\right)\)
1) x2 + 5x - 6
= (x2 - x) + (6x - 6)
= x(x - 1) + 6(x - 1)
= (x - 1)(x + 6)
2) 5x2 + 5xy - x - y
= (5x2 + 5xy) + (-x - y)
= -(x + y) + 5x(x + y)
= (x + y)(5x - 1)
3) 7x - 6x2 - 2
= -(6x2 - 7x + 2)
= -(2x - 1)(3x - 2)
phân tích thành nhân tử
a, x2 + 5x - 6
b, 5x2 + 5xy - x - y
c, 7x - 6x2 - 2
Ta có : x2 - x + 6x - 6
= x(x - 1) + 6(x - 1)
= (x + 6)(x - 1)
b) 5x2 + 5xy - x - y
= 5x(x + y) - (x + y)
= (5x - 1)(x + y)
câu a,b làm như trên. câu c:
c, 7x - 6x2 - 2 = -6x^2 + 7x - 2 = -( 6x^2-3x-4x+2) = -[ 3x ( 2x-1)-2(2x-1)]=-(3x-2)(2x-1)
Phân tích thành nhân tử
a) x^2+5x-6
b) 5x^2+5xy-x-y
c) 7x-6x^2-2
d) x^2+4x+3
e) 2x^2+3x-5
f) 16x-5x^2-3
giải chi tiết
nhiều quá, các bn ngại làm, chia nhỏ ra,mk làm cho 2 câu
a) x2 +5x -6 = x2 -x +x + 5x -6
= x2 -x +6x -6
= x( x-1) + 6(x-1) = (x-1)(x+6)
b) 5x2 +5xy -x-y = 5x(x+y) -(x+y)
= (x+y)(5x-1)
e) \(2x^2+3x-5\)
\(=2x^2+5x-2x-5\)
\(=x\cdot\left(2x+5\right)-\left(2x+5\right)\)
\(=\left(x-1\right)\left(2x+5\right)\)
f) \(16x-5x^2-3\)
\(=-5x^2+16x-3\)
\(=-5x^2+15+x-3\)
\(=-5\cdot\left(x-3\right)+x-3\)
\(=\left(-5x+1\right)\left(x-3\right)\)
c)7x-\(6x^2\)-2
=3x + 4x - \(6x^2\) - 2
=(3x - \(6x^2\)) - (2 - 4x)
= 3x(1 - 2x) - 2(1 - 2x)
=(1-2x)(3x-2)
Phân tích thành nhân tử
\(x^2+5x-6\)
\(5x^2+5xy-x-y\)
\(7x-6x^2-2\)
\(x^2+5x-6=x^2-6x+x-6=x\left(x-6\right)+\left(x-6\right)=\left(x+1\right)\left(x-6\right)\)
\(5x^2+5xy-x-y=5x\left(x+y\right)-\left(x+y\right)=\left(5x-1\right)\left(x+y\right)\)
\(7x-6x^2-2=-6x^2+7x-2=-6\left(x^2-\frac{7}{6}x+\frac{1}{3}\right)=-6\left(x^2-\frac{7}{6}x+\frac{49}{144}-\frac{1}{144}\right)=-6\left[\left(x-\frac{7}{12}\right)^2-\frac{1}{144}\right]\)
1) x2-x+6x-6 = x(x-1)+6(x-1)=(x+6)(x-1)
2) 5x(x+y)-(x+y) =(5x-1)(x+y)
3) -6x2+7x-2 = -6x2+3x+4x-2= -6x(x-\(\frac{1}{2}\)) +4(x-\(\frac{1}{2}\)) =(-3x+2)(2x-1)
Phân tích đa thức thành nhân tử:
1, x^3-x+y^3-4
2, 4x^2-y^2+4x+1
3, x^4+2x^3+x^2
4, x^2+5x-6
5, 7x-6x^2-2
6, 5x^2+5xy-x-y
7, 2x^2+3x-5
8,x^4-5x^2+4
9, x^3-5x^2+45-9x
10, x^4-2x^3-2x^2-2x-3
11, 81x^4+4
12,x^5+x+1
13, x^4+6x^3+7x^2-6x+1
14, x(x+4)(x+6)(x+10)+128
2: =(2x+1)^2-y^2
=(2x+1+y)(2x+1-y)
3: =x^2(x^2+2x+1)
=x^2(x+1)^2
4: =x^2+6x-x-6
=(x+6)(x-1)
5: =-6x^2+3x+4x-2
=-3x(2x-1)+2(2x-1)
=(2x-1)(-3x+2)
6: =5x(x+y)-(x+y)
=(x+y)(5x-1)
7: =2x^2+5x-2x-5
=(2x+5)(x-1)
8: =(x^2-1)*(x^2-4)
=(x-1)(x+1)(x-2)(x+2)
9: =x^2(x-5)-9(x-5)
=(x-5)(x-3)(x+3)
Câu 15. Kết quả phân tích đa thức 6x 2 + 6xy + 7x + 7y thành nhân tử là :
A. (7x+y)(5x+y)
B. ( 3x +5 ) (x+y)
C. ( x+y ) ( 6x + 7)
D. ( 7x +6)( x + y)
Phân tích đa thức thành nhân tử bằng cách phối hợp nhiều phương pháp.
1/ x2 + 5x - 6
2/ 5x2 + 5xy x - y
3/ 7x - 6x2 - 2
\(1,x^2+5x-6=x^2-x+6x-6=x\left(x-1\right)+6\left(x-1\right)=\left(x-1\right)\left(x+6\right)\)
\(3,7x-6x^2-2=-6x^2+7x-2=-6x^2+3x+4x-2=3x\left(-2x+1\right)+2\left(2x-1\right)\)
\(=3x\left(1-2x\right)-2\left(1-2x\right)=\left(1-2x\right)\left(3x-2\right)\)
\(2,5x^2+5xy-x-y=5x\left(x+y\right)-\left(x+y\right)=\left(x+y\right)\left(5x-1\right)\)
a)x^2+5x+6
b5x^2+5xy-x-y
c,7x-6x^2-2
phân tích thành nhân tử bằng 4 cách khác nhau
a: =x^2+2x+3x+6
=(x+2)(x+3)
b: =5x(x+y)-(x+y)
=(x+y)(5x-1)
c: =-6x^2+3x+4x-2
=-3x(2x-1)+2(2x-1)
=(2x-1)(-3x+2)