thực hiện phép tính:
\(\left(5x^2+9xy-2y^2\right):\left(5x-2\right)\)
thực hiện phép tính: \(5x^2+9xy-2y^2:\left(x+2y\right)\)
Ta có :
\(\left(5x^2+9xy-2y^2\right):\left(x+2y\right)\)
\(=[\left(5x^2+10xy)-(xy+2y^2\right)]:\left(x+2y\right)\)
\(=[5x\left(x+2y)-y(x+2y\right)]:\left(x+2y\right)\)
\(=\left(5x-y\right)(x+2y):\left(x+2y\right)\)
\(=5x-y\)
Ta phân tích đa thức chia thành nhân tử :
5x2 + 9xy - 2y2
= 5x2 + 10xy - xy - 2y2
= 5x( x + 2y) - y( x + 2y)
= ( 5x - y)( x + 2y)
Khi đó , ta có thương là : 5x - y
\(2\left(3+5x\right)^2-3\left(3x-5\right)^2-\left(3+5x\right)\left(5x-3\right)\)
Thực hiện phép tính
\(2\left(3+5x\right)^2-3\left(3x-5\right)^2-\left(3+5x\right)\left(5x-3\right)\)
\(=2\left(9+30x+25x^2\right)-3\left(9x^2-30x+25\right)^2-\left(25x^2-9\right)\)
\(=18+60x+50x^2-27x^2+90x-75-25x^2+9\)
\(=-2x^2+150x-48\)
\(=-x^2+75x-24\)
Thực hiện phép tính
a, \(A=\left(3x^2y-11x^2-5y\right)\left(8xy-5x+6\right)\)
b,\(B=\left(-4x^2y-5x^2+3y^2\right)\left(2x^2-xy+3y^2\right)\)
c,\(C=5\left(2x-1\right)^2+4\left(x-1\right)\left(x+3\right)-2\left(3x-1\right)\left(3x+1\right)\)
A= 3x2 y-11x2-5y.8xy-5+6
=(3-11-5.8-5+6).(x2.x2.x).(y.y.y)
=-47x5y3
Làm phép chia:
\(a,15x^3y^5z:5x^2y^3\)
\(b,12x^4y^2:\left(-9xy^2\right)\)
\(c,\left(30x^4y^3-25x^2y^3-3x^4y^4\right):5x^2y^3\)
\(d,\left(4x^4-8x^2y^2+12x^5y\right):\left(-4x^2\right)\)
a, 15x3y5z : 5x2y3 = 3xy2z.
b, 12x4y2 : ( - 9xy2 ) = \(\frac{3}{4}x^3\).
c, ( 30x4y3 - 25x2y3 - 3x4y4 ) : 5x2y3 = \(6x^2-5-\frac{3}{5}x^2y.\)
d, ( 4x4 - 8x2y2 + 12x5y ) : ( - 4x2 ) = -x2 + 2y2 - 3x3y.
Thực hiện phép tính:
a) \(\dfrac{2}{5}xy\left(x^2y-5x+10y\right)\)
b) \(\left(x^2-1\right)\left(x^2+2x+y\right)\)
c) \(\left(x+3y\right)^2\)
d) \(\left(4x-y\right)^3\)
e) \(\left(x^2-2y\right)\left(x^2+2y\right)\)
g) \(18x^4y^2z:10x^4y\)
h) \(\left(x^3y^3+\dfrac{1}{2}x^2y^3-x^3y^2\right):\dfrac{1}{3}x^2y^2\)
i) \(\left(6x^3-7x^2-x+2\right):\left(2x+1\right)\)
k) \(\dfrac{5x-1}{3x^2y}+\dfrac{x+1}{3x^2y}\)
l) \(\dfrac{3x+1}{x^2-3x+1}+\dfrac{x^2-6x}{x^2-3x+1}\)
m) \(\dfrac{2x+3}{10x-4}+\dfrac{5-3x}{4-10x}\)
n) \(\dfrac{x}{x^2+2x+1}+\dfrac{3}{5x^2-5}\)
o) \(\dfrac{x^2+2}{x^3-1}+\dfrac{2}{x^2+x+1}+\dfrac{1}{1-x}\)
p) \(\dfrac{4x+2}{15x^3y}\dfrac{5y-3}{9x^2y}+\dfrac{x+1}{5xy^3}\)
q) \(\dfrac{2x-7}{10x-4}-\dfrac{3x+5}{4-10x}\)
r) \(\dfrac{3}{2x+6}-\dfrac{x-6}{2x^2+6x}\)
x) \(\dfrac{4y^2}{11x^4}.\left(-\dfrac{3x^2}{8y}\right)\)
y) \(\dfrac{x^2-4}{3x+12}.\dfrac{x+4}{2x-4}\)
z) \(\left(x^2-25\right):\dfrac{2x+10}{3x-7}\)
t) \(\left(\dfrac{2x+1}{2x-1}-\dfrac{2x-1}{2x+1}\right):\dfrac{4x}{10x-5}\)
w) \(\left(\dfrac{1}{x^2+x}-\dfrac{2-x}{x+1}\right):\left(\dfrac{1}{x}+x-2\right)\)
c: \(=x^2+6xy+9y^2\)
e: \(=x^4-4y^2\)
Thực hiện các phép nhân đơn thức sau:
a) \(\left( {4{x^3}} \right).\left( { - 6{x^3}y} \right)\) b) \(\left( { - 2y} \right).\left( { - 5x{y^2}} \right)\) c) \({\left( { - 2a} \right)^3}.{\left( {2ab} \right)^2}\)
`a)`
`4x^3 * (-6x^3y)`
`= 4*(-6) * (x^3*x^3) * y`
`= -24x^6y`
`b)`
`(-2y)*(-5xy^2)`
`= (-2)*(-5)*x*(y*y^2)`
`= 10xy^3`
`c)`
`(-2a)^3 * (2ab)^2`
`= (-8a^3) * (4a^2b^2)`
`= (-8*4)*(a^3*a^2)*b^2`
`= -32a^5b^2`
a) \(4x^3\cdot\left(-6x^3y\right)\)
\(=\left(4\cdot-6\right)\cdot\left(x^3\cdot x^3\right)\cdot y\)
\(=-24x^6y\)
b) \(\left(-2y\right)\cdot\left(-5xy^2\right)\)
\(=\left(-2\cdot-5\right)\cdot\left(y\cdot y^2\right)\cdot x\)
\(=10xy^3\)
c) \(\left(-2a\right)^3\cdot\left(2ab\right)^2\)
\(=-8a^3\cdot4a^2b^2\)
\(=\left(-8\cdot4\right)\cdot\left(a^3\cdot a^2\right)\cdot b^2\)
\(=-32a^5b^2\)
Thực hiện phép tính :
a) \(\left(5x-2y\right)\left(x^2-xy+1\right)\)
b) \(\left(x-1\right)\left(x+1\right)\left(x+2\right)\)
c) \(\dfrac{1}{2}x^2y^2\left(2x+y\right)\left(2x-y\right)\)
\(a,\left(5x-2y\right)\left(x^2-xy+1\right)=5x^3-5x^2y+5x-2x^2y-2xy^2-2y=5x^3-7x^2y-2xy^2+5x-2y\)\(b\left(x-1\right)\left(x+1\right)\left(x-2\right)=\left(x^2-1\right)\left(x+2\right)=x^3+2x^2-x-2\)\(c,\dfrac{1}{2}x^2y^2\left(2x+y\right)\left(2x-y\right)=\dfrac{1}{2}x^2y^2\left(4x^2-y^2\right)=2x^4y^2-\dfrac{1}{2}x^2y^4\)
b) \(\left(x-1\right)\left(x+1\right)\left(x+2\right)=\left(x^2-1\right)\left(x+2\right)\\ =x^3+2x^2-x-2\)
c) \(\dfrac{1}{2}x^2y^2\left(2x+y\right)\left(2x-y\right)=\dfrac{1}{2}x^2y^2\left(4x^2-y^2\right)\\ =2x^4y^2-\dfrac{1}{2}x^2y^4\)
Thực hiện phép tính:
\(\left(8-5x\right).\left(x+2\right)+4.\left(x-2\right).\left(x-1\right)+2.\left(x-2\right).\left(x+2\right)+10\)
(8 - 5x).(x + 2) + 4.(x - 2)(x - 1) + 2.(x - 2)(x + 2) + 10
= (8x + 16 - 5x2 - 10x) + 4.(x2 - 3x + 2) + 2.(x2 - 4) + 10
= 8x + 16 - 5x2 - 10x + 4x2 - 12x + 8 + 2x2 - 8 + 10
= (8x - 10x - 12x) + (-5x2 + 4x2 + 2x2) + (16 + 8 - 8 + 10)
= -14x + x2 + 26
Thực hiện các phép chia:
\(\left(x^3+3x^2y+3xy^2+y^3\right):2\left(x+y\right)^2\)
\(\left(3x^3-5x^2+9x-15\right):\left(3x-5\right)\)