Phân tích đa thức thành nhân tử:
x^4+x^3+6.x^2+5.x+5
x^4-2.x^3-12.x^2+12.x+36
X^8.y^8+x^4.y^4+1
Phân tích các đa thức sau thành nhân tử:
a) \({\left( {x - 1} \right)^2} - 4\)
b) \(4{x^2} + 12x + 9\)
c) \({x^3} - 8{y^6}\)
d) \({x^5} - {x^3} - {x^2} + 1\)
e) \( - 4{x^3} + 4{x^2} + x - 1\)
f) \(8{x^3} + 12{x^2} + 6x + 1\)
\(a,\left(x-1\right)^2-2^2=\left(x-1-2\right)\left(x-1+2\right)=\left(x-3\right)\left(x+1\right)\\ b,=\left(2x\right)^2+2.2x.3+3^2\\ =\left(2x+3\right)^2\\ c,=x^3-\left(2y\right)^3\\ =\left(x-2y\right)\left(x^2+2xy+4y^2\right)\\ d,=x^3\left(x^2-1\right)-\left(x^2-1\right)\\ =\left(x^3-1\right)\left(x^2-1\right)\\ =\left(x-1\right)\left(x^2+x+1\right)\left(x-1\right)\left(x+1\right)\\ =\left(x-1\right)\left(x+1\right)\left(x^2+x+1\right)\)
\(e,=-4x^2\left(x-1\right)+\left(x-1\right)\\ =\left(1-4x^2\right)\left(x-1\right)\\ =\left(1-2x\right)\left(1+2x\right)\left(x-1\right)\)
\(f,=\left(2x\right)^3+3.\left(2x\right)^2.1+3.2x.1^2+1^3\\ =\left(2x+1\right)^3\)
Phân tích thành nhan tử
a) x^4 +x^3+6.x^2+5.x+5
b) x^4-2.x^3-12-12.x^2+12.x+36
c) x^8.y^8+x^4.y^4+1
Ta có : x4 + x3 + 6x2 + 5x + 5
= (x4 + 5x2) + (x3 + 5x) + (x2 + 5)
= x2(x2 + 5) + x(x2 + 5) + (x2 + 5)
= (x2 + 5)(x2 + x + 1)
B1:Phân tích đa thức thành nhân tử:
1)x2-7x+10
2)x2+3x-5
3)2x2+3x-5
4)2x2+x-6
5)3x2+4x-4
6)3x2-10x-8
7)15x2-11x+2
8)6x2+5x-6
B2:Phân tích đa thức thành nhân tử:
1)(x2+x+1)(x2+x+2)-12
2)x2+2xy+y2-x-y-12
3)x(x+4)(x+6)(x+10)+128
4)x2-2xy+y2+3x-3y-4
B3:Phân tích đa thức thành nhân tử:
a)x2-xz-9y2+3yz
b)x3-x2-5x+125
c)x4-25x2+20x-4
a) x2 + 6x + 9 = x2 + 2 . x . 3 + 32 = (x + 3)2
b) 10x – 25 – x2 = -(-10x + 25 +x2) = -(25 – 10x + x2)
= -(52 – 2 . 5 . x – x2) = -(5 – x)2
c) 8x3 - 1/8 = (2x)3 – (1/2)3 = (2x - 1/2)[(2x)2 + 2x . 12 + (1/2)2]
= (2x - 1/2)(4x2 + x + 1/4)
d)1/25x2 – 64y2 = (1/5x)2(1/5x)2- (8y)2 = (1/5x + 8y)(1/5x - 8y)
\(x^2-7x+10\)
\(=x^2-2x-5x+10\)
\(=x\left(x-2\right)-5\left(x-2\right)\)
\(=\left(x-2\right)\left(x-5\right)\)
học tốt
Phân tích đa thức thành nhân tử:
1.45+x^3-5*x^2-9*x
2.x^4-2*x^3-2*x^2-2*x+3
3.x^4-5*x^2+4
4.x^4+64
5.x^5+x^4+1
6.(x^2+2*x)*(x^2+2*x+4)+3
7.(x^3+4*x+8)^2+3*x*(x^2+4*x+8)+2*x^2
8. x^3*(x^2-7)^2-36*x
9.x^5+x+1
10. x^8+x^4+1
11. x^5-x^4-x^3-x^2-x-2
12. x^9-x^7-x^6-x^5+x^4+x^3+x^2-1
13. (x^2-x)^2-12*(x^2-x)+24
1, \(45+x^3-5x^2-9x=9\left(5-x\right)+x^2\left(x-5\right)\)
\(=\left(9-x^2\right)\left(x-5\right)=\left(3-x\right)\left(x+3\right)\left(x-5\right)\)
3, \(x^4-5x^2+4\)
Đặt \(x^2=t\left(t\ge0\right)\)ta có :
\(t^2-5t+4=t^2-t-4t+4=t\left(t-1\right)-4\left(t-1\right)\)
\(=\left(t-4\right)\left(t-1\right)=\left(x^2-4\right)\left(x^2-1\right)=\left(x-2\right)\left(x+2\right)\left(x-1\right)\left(x+1\right)\)
`Answer:`
1. `45+x^3-5x^2-9x`
`=x^3+3x^2-8x^2-24x+15x+45x`
`=x^2 .(x+3)-8x.(x+3)+15.(x+3)`
`=(x+3).(x^2-8x+15)`
`=(x+3).(x^2-5x-3x+15)`
`=(x-3).(x-5).(x-3)`
2. `x^4-2x^3-2x^2-2x-3`
`=x^4+x^3-3x^3+x^2+x-3x-3`
`=x^3 .(x+1)-3x^2 .(x+1)+x.(x+1)-3.(x+1)`
`=(x+1).(x^3-3x^2+x-3)`
`=(x+1).[x^3 .(x-3).(x-3)]`
`=(x+1).(x-3).(x^2+1)`
3. `x^4-5x^2+4`
`=x^4-x^2-4x^2+4`
`=x^2 .(x^2-1)-4.(x^2-1)`
`=(x^2-1).(x^2-4)`
`=(x-1).(x+1).(x-2).(x+2)`
4. `x^4+64`
`=x^4+16x^2+64-16x^2`
`=(x^2+8)^2-16x^2`
`=(x^2+8-4x).(x^2+8+4x)`
5. `x^5+x^4+1`
`=x^5+x^4+x^3-x^3+1`
`=x^3 .(x^2+x+1)-(x^3-1)`
`=x^3 .(x^2+x+1)-(x-1).(x^2+x+1)`
`=(x^2+x+1).(x^3-x+1)`
6. `(x^2+2x).(x^2+2x+4)+3`
`=(x^2+2x)^2+4.(x^2+2x)+3`
`=(x^2+2x)^2+x^2+2x+3.(x^2+2x)+3`
`=(x^2+2x+1).(x^2+2x)+3.(x^2+2x+1)`
`=(x^2+2x+1).(x^2+2x+3)`
`=(x+1)^2 .(x^2+2x+3)`
7. `(x^3+4x+8)^2+3x.(x^2+4x+8)+2x^2`
`=x^6+8x^4+16x^3+16x^2+64x+64+3x^3+12x^2+24x+2x^2`
`=x^6+8x^4+19x^3+30x^2+88x+64`
8. `x^3 .(x^2-7)^2-36x`
`=x[x^2.(x^2-7)^2-36]`
`=x[(x^3-7x)^2-6^2]`
`=x.(x^3-7x-6).(x^3-7x+6)`
`=x.(x^3-6x-x-6).(x^3-x-6x+6)`
`=x.[x.(x^2-1)-6.(x+1)].[x.(x^2-1)-6.(x-1)]`
`=x.(x+1).[x.(x-1)-6].(x-1).[x.(x+1)-6]`
`=x.(x+1).(x-1).(x^2-3x+2x-6).(x^2+3x-2x-6)`
`=x.(x+1).(x-1).[x.(x-3)+2.(x-3)].[x.(x+3)-2.(x+3)]`
`=x.(x+1)(x-1).(x-2).(x+2).(x-3).(x+3)`
9. `x^5+x+1`
`=x^5-x^2+x^2+x+1`
`=x^2 .(x^3-1)+(x^2+x+1)`
`=x^2 .(x-1).(x^2+x+1)+(x^2+x+1)`
`=(x^2+x+1).(x^3-x^2+1)`
10. `x^8+x^4+1`
`=[(x^4)^2+2x^4+1]-x^4`
`=(x^4+1)^2-(x^2)^2`
`=(x^4-x^2+1).(x^4+x^2+1)`
`=[(x^4+2x^2+1)-x^2].(x^4-x^2+1)`
`=[(x^2+1)^2-x^2].(x^4-x^2+1)`
`=(x^2-x+1).(x^2+x+1).(x^4-x^2+1)
11. ` x^5-x^4-x^3-x^2-x-2`
`=x^5-2x^4+x^4-2x^3+x^3-2x^2+x^2-2x+x-2`
`=x^4 .(x-2)+x^3 ,(x-2)+x^2 .(x-2)+x.(x-2)+(x-2)`
`=(x-2).(x^4+x^3+x^2+x+1)`
12. `x^9-x^7-x^6-x^5+x^4+x^3+x^2-1`
`=(x^9-x^7)-(x^6-x^4)-(x^5-x^3)+(x^2-1)`
`=x^7 .(x^2-1)-x^4 .(x^2-1)-x^3 .(x^2-1)+(x^2-1)`
`=(x^2-1).(x^7-x^4-x^3+1)`
`=(x-1)(x+1)(x^3-1)(x^4-1)`
`=(x-1)(x+1)(x^2+x+1)(x-1)(x^2-1)(x^2+1)`
`=(x-1)^2 .(x+1)(x^2+x+1)(x-1)(x+1)(x^2+1)`
`=(x-1)^3 .(x+1)^2 .(x^2+x+1)(x^2+1)`
13. `(x^2-x)^2-12(x^2-x)+24`
`=[ (x^2-x)^2-2.6(x^2-x)+6^2]-12`
`=(x^2-x+6)^2-12`
`=(x^2-x+6-\sqrt{12})(x^2-x+6+\sqrt{12})`
Bài 5. Phân tích các đa thức thành nhân tử
a) (x2-4x)2-8(x2-4x)+15 b) (x2+2x)2+9x2+18x+20
c) ( x+1)(x+2)(x+3)(x+4)-24 d) (x-y+5)2-2(x-y+5)+1
Bài 6. Phân tích các đa thức thành nhân tử
a) x2y+x2-y-1 b) (x2+x)2+4(x2+x)-12
c) (6x+5)2(3x+2)(x+1)-6
Cưu là mình vs (x^2+x)^2-2(x^2+x)-15
Phân tích đa thức thành nhân tử
1) x^3 - 7x + 6
2) x^3 - 9x^2 + 6x + 16
3) x^3 - 6x^2 - x + 30
4) 2x^3 - x^2 + 5x + 3
5) 27x^3 - 27x^2 + 18x - 4
6) x^2 + 2xy + y^2 - x - y - 12
7) (x + 2)(x +3)(x + 4)(x + 5) - 24
8) 4x^4 - 32x^2 + 1
9) 3(x^4 + x^2 + 1) - (x^2 + x + 1)^2
10) 64x^4 + y^4
11) a^6 + a^4 + a^2b^2 + b^4 - b^6
12) x^3 + 3xy + y^3 - 1
13) 4x^4 + 4x^3 + 5x^2 + 2x + 1
14) x^8 + x + 1
15) x^8 + 3x^4 + 4
16) 3x^2 + 22xy + 11x + 37y + 7y^2 +10
17) x^4 - 8x + 63
đúng nhiều nhất sẽ đc tick
Ta có : x3 - 7x + 6
= x3 - x - 6x + 6
= x(x2 - 1) - 6(x - 1)
= x(x + 1)(x - 1) - 6(x - 1)
= (x - 1) [x(x + 1) - 6]
= (x - 1) (x2 + x - 6) .
CÁC Ý SAU TƯƠNG TỰ
x3 - 7x + 6
= x3 - x - 6x + 6
= x(x2 - 1) - 6(x - 1)
= x(x + 1)(x - 1) - 6(x - 1)
= (x - 1) [x(x + 1) - 6]
= (x - 1) (x2 + x - 6) .
1. Phân tích đa thức thành nhân tử
1) y^2-13y+12
2) y^2-13y+12
3) x^2-x-30
4) y^2+y-42
5) x^2+3x-10
6)x^2-8x+15
7) 2x^2-y^2+xy
8) x^2+x-6
9) y^2-y-12
11) x^2+3x+2
12) x^2-3xy+2y^2
13) x^2-5x+6
14) x^4+x^2+2x
15) x^4+4
16) x^4+x^2+1
17) x^2+x-2
\(\left(1+2\right),y^2-13y+12=y^2-12y-y-12=y\left(y-12\right)+\left(y-12\right)=\left(y+1\right)\left(y-12\right)\)
\(3,x^2-x-30=x^2-6x+5x-30=x\left(x-6\right)+5\left(x-6\right)=\left(x+5\right)\left(x-6\right)\)
\(4,y^2+y-42=y^2-6y+7y-42=y\left(y-6\right)+7\left(y-6\right)=\left(y+7\right)\left(y-6\right)\)
\(5,x^2+3x-10=x^2-2x+5x-10=x\left(x-2\right)+5\left(x-2\right)=\left(x+5\right)\left(x-2\right)\)
\(6,x^2-8x+15=x^2-5x-3x+15=x\left(x-5\right)-3\left(x-5\right)=\left(x-3\right)\left(x-5\right)\)
Phân tích đa thức thành nhân tử a) A = x . y - x^2 - y^2 + 4 . x + 5
b) B = 19 . x^2 + 54 . y^2 + 16 . z^2 - 16 . x . z -24 .y . z +36 . x . y + 5
c) C = x . y . ( x - 2 ) . ( y + 6 ) + 12 . x^2 - 24 . x + 3 . y^2 + 18 . y + 2016
d) 12.x^4 +3.x^3+x^2-2
e) x^4+3x^3-x^2-4x+2
g) x^4+6x^3+7x^2-6x+1
h)x^9-x^7-x^6-x^5+x^4+x^3+x^2+1
tim a,b,c,d thoa man a^2+b^2+c^2+d^2-ab-bc-cd-d+2/5=0