2a2x-5by-5a2y+2bx
Đa thức 2 a 2 x – 5 b y – 5 a 2 y + 2 b x được phân tích thành
A. a 2 + b 5 x – 2 y
B. a 2 – b 2 x – 5 y
C. a 2 + b 2 x + 5 y
D. a 2 + b 2 x – 5 y
Ta có
2 a 2 x – 5 b y – 5 a 2 y + 2 b x = 2 a 2 x – 5 a 2 y + 2 b x – 5 b y = a 2 2 x – 5 y + b 2 x – 5 y = a 2 + b 2 x – 5 y
Đáp án cần chọn là: D
phân tích đa thức thành nhân tử
a) x4+2x2+1
b) 3ax2+3bx2+ax+bx+5a+5b
c) ax2-bx2-2ax+2bx-3a+3b
d) 10xy2-5by2+2a2x-aby
a) x4+2x2+1=(x2+1)2
b)=3x2(a+b)+x(a+b)+5(a+b)=(a+b)(3x2+x+5)
c)=x2(a-b)-2x(a-b)-3(a-b)=(a-b)(x2-2x-3)=(a-b)(x-3)(x+1)
d)=2x(y2-a2)-5by(y+a)=(y+a)(2xy-2xa-5by)
\(\text{a) x}^4+2x^2+1=\left(x^2+1\right)^2\)
\(\text{b) 3}ax^2+3bx^2+ãx+bx+5a+5b=\left(3ax^2+3bx^2\right) +\left(ax+bx\right)+\left(5a+5b\right)=3x^2+x\left(a+b\right)+5\left(a+b\right)=\left(a+b\right)\left(3x^2+x+5\right)\)
\(\text{c) a}x^2-bx^2-2ax+2bx-3a+3b=\left(\text{a}x^2-bx^2\right)-\left(2ax-2bx\right)-\left(3a-3b\right)=x^2\left(a-b\right)-2x\left(a-b\right)-3\left(a-b\right)=\left(x^2-2x-3\right)\left(a-b\right)\)
a) \(x^4+2x^2+1\)
\(=x^2\left(x^2+1\right)+\left(x^2+1\right)\)
\(=\left(x^2+1\right)^2\)
b) \(3ax^2+3bx^2+ax+bx+5a+5b\)
\(=3x^2\left(a+b\right)+x\left(a+b\right)+5\left(a+b\right)\)
\(=\left(a+b\right)\left(3x^2+x+5\right)\)
c) \(ax^2-bx^2-2ax+2bx-3a+3b\)
\(=x^2\left(a-b\right)-2x\left(a-b\right)-3\left(a-b\right)\)
\(=\left(a-b\right)\left(x^2-2x-3\right)\)
\(=\left(a-b\right)\left(x-3\right)\left(x+1\right)\)
Câu d mình chịu
Phân tích đa thức thành nhân tử
x^2-xy+2x-2y
ax+ay-2x-2y
ax^2-3axy+bx-3by
2a^2-5by-5a^2y+2bx
x2-xy+2x-2y
= (x2-xy)+(2x-2y)
= x(x-y)+2(x-y)
= (x-y)(x+2)
ax+ay-2x-2y
= (ax+ay)-(2x+2y)
= a(x+y)-2(x+y)
=(x+y)(a-2)
ax2-3axy+bx-3by
= (ax2+bx)-(3axy+3by)
= x(ax+b)-3y(ax+b)
= (ax+b)(x-3y)
2a2-5by-5a2y+2bx
= (2a2-5a2y)+(2bx-5by)
= a2(2-5y)+b(2x-5y)
x2-xy+2x-2y=(x2-xy)+(2x-2y)=x(x-y)+2(x-y)=(x-y)(x+2)
ax+ay-2x-2y=(ax+ay)-(2x+2y)=a(x+y)-2(x+y)=(x+y)(a-2)
ax2-3axy+bx-3by=(ax2+bx)-(3axy+3by)=x(ax+b)-3y(ax+b)=(ax+b)(x-3y)
Phân tích đa thức thành nhân tử :
1) x( a-b) + a - b
2) x ( a+ b ) - a - b
3 ) 10 ax - 5ay - 2x + y
4 ) \(2a^2x-5by-5a^2y+2bx\)
5 ) \(2ax^2-bx^2-2ax+bx+4a-2b\)
Giups mình vs . mai p nộp r TT
a, x(a - b) + (a - b)
= (x + 1)(a - b)
b, x(a + b) - a - b
= x(a + b) - (a + b)
= (x - 1)(a + b)
c, 10ax - 5ay - 2x + y
= 5a(2x - y) - (2x - y)
= (5a - 1)(2x - y)
d, 2a^2x - 5by - 5a^2y + 2bx
= 2x(a^2 + b) - 5y(b + a^2)
= (2a - 5y)(a^2 + b)
làm tiếp:
2ax2 - bx2 - 2ax +bx +4a-2b
= x2(2a-b) - x(2a-b) +2(2a-b)
=(2a-b)(x2-x+2)
1)\(x\left(a-b\right)+a-b=x\left(a-b\right)+\left(a-b\right)=\left(a-b\right)\left(a+x\right)\)
2)\(x\left(a+b\right)-a-b=x\left(a+b\right)-\left(a+b\right)=\left(a+b\right)\left(x-1\right)\)
3)\(10ax-5ay-2x+y=\left(10ax-5ay\right)-\left(2x-y\right)=5a\left(2x-y\right)-\left(2x-y\right)=\left(2x-y\right)\left(5a-1\right)\)
4)\(2a^2x-5by-5a^2y+2bx=\left(2a^2x-5a^2y\right)+\left(2bx-5by\right)=a^2\left(2x-5y\right)+b\left(2x-5y\right)=\left(2x-5y\right)\left(a^2+b\right)\)5)\(2ax^2-bx^2-2ax+bx+4a-2b=\left(2ax^2-bx^2\right)-\left(2ax-bx\right)+\left(4a-2b\right)=x^2\left(2a-b\right)-x\left(2a-b\right)+2\left(2a-b\right)\)\(=\left(2a-b\right)\left(x^2-x+2\right)\)
Kết quả của phép tính ( a x 2 + b x – c ) . 2 a 2 x bằng
A. 2 a 4 x 3 + 2 a 2 b x 2 – 2 a 2 c x
B. 2 a 3 x 3 + b x – c
C. 2 a 4 x 2 + 2 a 2 b x 2 – a 2 c x
D. 2 a 3 x 3 + 2 a 2 b x 2 – 2 a 2 c x
Bài 2/ Phân tích các đa thức sau thành nhân tử ( phương pháp nhóm hạng tử)
Câu 31) 2a2x - 5by - 5a2y + 2bx ;
Câu 34) 4acx + 4bcx + 4ax + 4bx ;
Câu 37) 3ax2 - bx2 - 2ax + bx + 4a - 2b ;
Lời giải:
31.
\(2a^2x-5by-6a^2y+2bx=(2a^2x+2bx)-(5by+5a^2y)\)
\(=2x(a^2+b)-5y(b+a^2)=(a^2+b)(2x-5y)\)
34.
\(4acx+4bcx+4ax+4bx=4x(ac+bc+a+b)\)
\(=4x[(ac+bc)+(a+b)]=4x[c(a+b)+(a+b)]=4x(c+1)(a+b)\)
37. Sửa đề:
\(2ax^2-bx^2-2ax+bx+4a-2b\)
\(=(2ax^2-bx^2)-(2ax-bx)+(4a-2b)\)
\(=x^2(2a-b)-x(2a-b)+2(2a-b)=(2a-b)(x^2-x+2)\)
Lời giải:
31.
\(2a^2x-5by-6a^2y+2bx=(2a^2x+2bx)-(5by+5a^2y)\)
\(=2x(a^2+b)-5y(b+a^2)=(a^2+b)(2x-5y)\)
34.
\(4acx+4bcx+4ax+4bx=4x(ac+bc+a+b)\)
\(=4x[(ac+bc)+(a+b)]=4x[c(a+b)+(a+b)]=4x(c+1)(a+b)\)
37. Sửa đề:
\(2ax^2-bx^2-2ax+bx+4a-2b\)
\(=(2ax^2-bx^2)-(2ax-bx)+(4a-2b)\)
\(=x^2(2a-b)-x(2a-b)+2(2a-b)=(2a-b)(x^2-x+2)\)
Câu 31:
\(2a^2x-5by-5a^2y+2bx\)
\(=2x\left(a^2+b\right)-5y\left(a^2+b\right)\)
\(=\left(a^2+b\right)\left(2x-5y\right)\)
Câu 34:
\(4acx+4bcx+4ax+4bx\)
\(=4cx\left(a+b\right)+4x\left(a+b\right)\)
\(=\left(a+b\right)\left(4cx+4x\right)\)
\(=4x\left(a+b\right)\left(c+1\right)\)
Câu 37:
\(2ax^2-bx^2-2ax+bx+4a-2b\)
\(=x^2\left(2a-b\right)-x\left(2a-b\right)+2\left(2x-b\right)\)
\(=\left(2a-b\right)\left(x^2-x+2\right)\)
\(=\left(2a-b\right)\left(x^2-x+2\right)\)
Bài 1.Phân tích các đa thức thành nhân tử( phương pháp nhóm hạng tử)
1.5x2y + 5xy2 - a2x + a2y
2. 6a2y - 3aby + 4a2x - 2bx
3. 2x2 - 6xy + 5x - 15y
4. 10ay2 - 5by2 + 2a2 - aby
5.ax2 -3axy + 3ay2 - 3axy
6. 2a2 - 5by -5a2y + 2bx
Mong các bạn giúp mik
1) \(5x^2y+5xy^2-a^2x+a^2y\)
\(=5xy\left(x-y\right)-a^2\left(x-y\right)\)
\(=\left(x-y\right)\left(5xy-a^2\right)\)
2) \(6a^2y-3aby+4a^2x-2bx\)
\(=3ay\left(2a-b\right)+2x\left(2a-b\right)\)
\(=\left(2a-b\right)\left(3ay+2x\right)\)
p/s: mấy câu kia nhỏ quá mk k đọc đc
1, 6a^2y-3aby+4a^2x-2abx
2, 5x^2y-5xy^2-a^2x+a^2y
3, 2x^2-6xy+5x-15y
4, ax^2-5by-5a^2y+2bx
5, 2ax^3+6ax^2+6ax+18a
6, ax^2-bx^2y-ã+bx+2a-2b
7,3ax^2+3bx^2+ã+bx+5a=5b
8, ax^2-bx^2-2ax+2bx-3a+3b
9, 2ax^2-bx^2-2ax+bx-3a+3b
10, 2ax^2-5x^2-ax+bx+4a-2b
11,ax^2-5x^2-ax+5x+a-5
Phân tích đa thức sau bằng phương pháp nhóm hạng tử
1) x ( a - b ) + a - b ; 2) x - y - a( x - y ) ; 3) a( x + y ) - x - y ; 4) x( a - b ) - a + b ; 5) x\(^2\) + xy - 2x - 2y
6) 10ax - 5ay + 2x - y ; 7) 2a\(^{^2}\) x - 5by - 5a\(^2\) y + 2bx ; 8) 2ax\(^2\)- bx\(^2\) - 2ax + bx + 4a - 2b ; 9) 2ax - bx + 3cx - 2a + b - 3c
10) ax - bx - 2cx - 2a + 2b + 4c
Giúp mik đi
1, x(a-b)+a-b 2, x-y-a(x-y) 3, a(x+y)-x-y 4, x(a-b)-a+b 5, x2+xy-2x-2y 6, 10ax-5ay+2x-y
= x(a-b)+(a-b) =(x-y)-a(x-y) =a(x+y)-(x+y) =x(a-b)-(a-b) =(x2+xy)-(2x+2y) =(10ax+2x)-(5ay+y)
=(a-b)(x+1) =(x-y)(1-a) =(x+y)(a-1) =(a-b)(x-1) =x(x+y)-2(x+y) =2x(5a+1)-y(5a+1)
=(x+y)(x-2) =(5a+1)(2x-y)
7, 2a2x-5by-5a2y+2bx 8, 2ax2-bx2-2ax+bx+4a-2b 9, 2ax-bx+3cx-2a+b-3c 10, ax-bx-2cx-2a+2b+4c
=(2a2x+2bx)-(5by+5a2y) =(2ax2-bx2)-(2ax-bx)+(4a-2b) =(2ax-2a)-(bx-b)+(3cx-3c) =(ax-2a)-(bx-2b)-(2cx-4c)
=2x(a2+b)-5y(b+a2) =x2(2a-b)-x(2a-b)+2(2a-b) =2a(x-1)-b(x-1)+3c(x-1) =a(x-2)-b(x-2)-2c(x-2)
=(a2+b)(2x-5y) =(2a-b)(x2-x+2) =(x-1)(2a-b+3c) =(x-2)(a-b-2c)