Bài 2: Rút gọn:
a, \(x^4y-5xy^3+2xy^3-5x^4y\) b, 5xy4 - 5xy + 7xy - 2xy4
Tính :
a) \(x^4y-5xy^3+2xy^3-5x^4y\)
b) \(10x3y5-5xy+5x3y5+8xy\)
c) \(5xy^2\left(\frac{-3}{10}x^2y\right)+\frac{3}{4}x^3y^3\)
d) \(\frac{2}{5}x^4y^5\left(\frac{5}{4}x^2y^3\right)+\frac{5}{2}x^2y^3\left(\frac{-9}{10}x^4y^5\right)\)
e) \(-5x^2y+12xy^2+7xy-10xy+3x^2y-4xy^2\)
CÁC PN GIÚP MIK NHA ! GHI RÕ RA GIÚP ! THANK YOU VERY MUCH ! ^_<
a/=X^4*y*(1-5)+(2-5)*X*Y^3
=X^4*y*-4+-3*X*Y^3
tạm thời tớ giúp được thế thôi.để tớ còn làm nốt ba bài hình cô giao đã
Bài 3:
3: \(6x\left(x-y\right)-9y^2+9xy\)
\(=6x\left(x-y\right)+9xy-9y^2\)
\(=6x\left(x-y\right)+9y\left(x-y\right)\)
\(=\left(x-y\right)\left(6x+9y\right)\)
\(=3\left(2x+3y\right)\left(x-y\right)\)
Bài 4:
a, 5xy*(3x+9y)
b, (2xy^2)*(x^4-2xy^2)
c, (5x^4y^3+7y^2)*(3x^2y-4xy^2)
d, (5x^2y-4x^2)*(3x+2y)
a) 3x(x+1)-x(3x+2)
b) 2x(x2-5x+6)+(x-1)(x+3)
c) (x2-xy+y2)-(x2+2xy+y2)
d) (2/5xy+x-y)-(3x+4y)-2/5xy
e) 2xy(x2-4xy+4y2)
f) (x+y)(xy+5)
g) (x3-2x2-x+2):(x-1)
h) (2x2+3x-2):(2x-1)
tìm xy thuộc z
a,5xy-3x-4y=8
b,2xy-5x-7y=13
c,2x+3y=5xy=12
LÀM ĐÚNG MÌNH TẶNG 3 TÍCH
Bài 7: Tìm Đa Thức A,B Biết a) 6x^2-3xy^2+A=x^2+y^2-2xy^2 b)B-(2xy-4y^2)=5xy+x^2-7y^2
a) 6x² + 3xy² + A = x² + y² - 2xy²
A = x² + y² - 2xy² - 6x² - 3xy²
A = (x² - 6x²) + (-2xy² - 3xy²) + y²
A = -5x² - 5xy² + y²
b) B - (2xy - 4y²) = 5xy + x² - 7y²
B = 5xy + x² - 7y² + 2xy - 4y²
B = (5xy + 2xy) + (-7y² - 4y²) + x²
B = 7xy - 11y² + x²
BT lam tinh nhan
a)(x^3+2x^2y-5xy^2-3y^3)(5x-4y)
b)(x+1)(x-2)(2x-1)
c)(2x+y)(4x^2-2xy+y^2)
d)(a^3+a^2b+ab^2+b^3)(a-b)
a: \(=5x^4-4x^3y+10x^3y-8x^2y^2-25x^2y^2+20xy^3-15xy^3+12y^4\)
\(=5x^4+6x^3y-33x^2y^2+5xy^3+12y^4\)
b: \(=\left(x^2-x-2\right)\left(2x-1\right)\)
\(=2x^3-x^2-2x^2+x-4x+2\)
\(=2x^3-3x^2-3x+2\)
c: \(=8x^3+y^3\)
d: \(=a^4-b^4\)
phân tích thành nhân tử a)2x(x-7)-5y(x-7)
b)5x^3y+10x^2y+5xy
c)4y^2-4y-x^2+1
d)x(x+1)(x+2)(x+3)+1
a) \(2x\left(x-7\right)-5y\left(x-7\right)=\left(x-7\right)\left(2x-5y\right)\)
b) \(5x^3y+10x^2y+5xy=5xy\left(x^2+2x+1\right)=5xy\left(x+1\right)^2\)
c) \(4y^2-4y-x^2+1=\left(2y-1\right)^2-x^2=\left(2y-1-x\right)\left(2y-1+x\right)\)
d) \(x\left(x+1\right)\left(x+2\right)\left(x+3\right)+1=\left(x^2+3x\right)\left(x^2+3x+2\right)+1\)
\(=\left(x^2+3x\right)^2+2\left(x^2+3x\right)+1=\left(x^2+3x+1\right)^2\)
a: \(=\left(x-7\right)\left(2x-5y\right)\)
b: \(=5xy\left(x^2+2x+1\right)=5xy\left(x+1\right)^2\)
a) \(=\left(2x-5y\right)\left(x-7\right)\)
b) \(=5xy\left(x^2+2x+1\right)=5xy\left(x+1\right)^2\)
c) \(=\left(\left(4y^2-4y+1\right)-x^2\right)=\left(2y-1\right)^2-x^2=\left(2y-1+x\right)\left(2y-1-x\right)\)
If x = 3 , y= -1 then x^5 + 5x^4y + 10x^3y^2 + 5xy^4 + y^2 = .....