Thực hiện các phép tính sau :
a) \(\dfrac{3}{2x+6}-\dfrac{x-6}{2x^2+6x}\)
b) \(\dfrac{1}{xy-x^2}-\dfrac{1}{y^2-xy}\)
BT10: Thực hiện phép tính
\(a,\dfrac{4}{5}y^2x^5-x^3.x^2y^2\)
\(b,-xy^3-\dfrac{2}{7}y^2.xy\)
\(c,\dfrac{5}{6}xy^2z-\dfrac{1}{4}xyz.y\)
\(d,15x^4+7x^4-20x^2.x^2\)
\(e,\dfrac{1}{2}x^5y-\dfrac{3}{4}x^5y+xy.x^4\)
\(f,13x^2y^5-2x^2y^5+x^6\)
a: =-1/5x^5y^2
b: =-9/7xy^3
c: =7/12xy^2z
d: =2x^4
e: =3/4x^5y
f: =11x^2y^5+x^6
Thực hiện phép tính:
a, \(\dfrac{x^2-1}{2x-y}+\dfrac{3x^2-3}{y-2x}-\dfrac{2x^2+7}{y-2x}\)
\(b,\dfrac{x+y}{1-xy}+\dfrac{x-y}{1-xy}-\dfrac{2x-3y}{xy-1}\)
Sao ảnh đại diện của bạn giống mình thế?
Thực hiện phép tính , rút gọn bt
\(\dfrac{2x+y}{2x^2-xy}+\dfrac{16x}{y^2-4x^2}+\dfrac{2x-y}{2x^2+xy}\)
\(\dfrac{x+y}{2\left(x-y\right)}+\dfrac{2}{x^2+3}+\dfrac{1}{x+1}\)
làm tính trừ \(\dfrac{5x+y}{xy-5x^2}\)-\(\dfrac{35x^2+8xy+y^2}{xy^225x^3}\)
thực hiện phép tính \(\dfrac{x^3+6x^2-25}{x^3+3x^2-10x}\)-\(\dfrac{x+5}{2x-x^2}\)
b: \(=\dfrac{x^3+6x^2-25}{x\left(x+5\right)\left(x-2\right)}+\dfrac{x+5}{x\left(x-2\right)}\)
\(=\dfrac{x^3+6x^2-25+x^2+10x+25}{x\left(x+5\right)\left(x-2\right)}=\dfrac{x^3+7x^2+10x}{x\left(x+5\right)\left(x-2\right)}=\dfrac{x+2}{x-2}\)
Thực hiện phép tính:
a) \(\dfrac{x+2y}{xy}\div\dfrac{x^2+4xy+4y^2}{2x^2}\)
b) \(\dfrac{4x^3-xy^2}{x^2+xy+y^2}\div\dfrac{\left(2x-y\right)^3}{x^3-y^3}\)
c) \(\dfrac{x+3}{x+2}\div\dfrac{3x+9}{2x-1}\div\dfrac{4x-2}{2x+4}\)
d) \(\dfrac{x+1}{x+2}\div\left(\dfrac{2x^2}{2x-3}\times\dfrac{3x+3}{4x^3}\right)\)
a: \(=\dfrac{x+2y}{xy}\cdot\dfrac{2x^2}{\left(x+2y\right)^2}=\dfrac{2x}{y\left(x+2y\right)}\)
b: \(=\dfrac{x\left(4x^2-y^2\right)}{x^2+xy+y^2}\cdot\dfrac{\left(x-y\right)\left(x^2+xy+y^2\right)}{\left(2x-y\right)^3}\)
\(=\dfrac{x\left(x-y\right)\left(2x+y\right)\left(2x-y\right)}{\left(2x-y\right)^3}\)
\(=\dfrac{x\left(x-y\right)\left(2x+y\right)}{\left(2x-y\right)^2}\)
c: \(=\dfrac{x+3}{x+2}\cdot\dfrac{2x-1}{3\left(x+3\right)}\cdot\dfrac{2\left(x+2\right)}{2\left(2x-1\right)}\)
=1/3
d: \(=\dfrac{x+1}{x+2}:\left(\dfrac{1}{2x}\cdot\dfrac{3x+3}{2x-3}\right)\)
\(=\dfrac{x+1}{x+2}\cdot\dfrac{2x\left(2x-3\right)}{3\left(x+1\right)}=\dfrac{2x\left(2x-3\right)}{3\left(x+2\right)}\)
thực hiện phép tính:
a) \(\dfrac{1}{2}\)x\(^3\) . (x\(^2\)-6\(^x\)-10)
b) -3x\(^2\) . ( 5x\(^3\)-4x\(^2\)+3x-1)
c) 3x . ( 5x\(^2\) - 2x - 1)
d) \(\dfrac{1}{2}\)x\(^2\)y . ( 2x\(^3\)-\(\dfrac{2}{5}\)xy\(^2\)-1)
a: =1/2x^3*x^2-1/2x^3*6x-1/2x^3*10
=1/2x^5-3x^4-5x^3
b: =-3x^2*5x^3+3x^2*4x^2-3x^2*3x+3x^2*3x
=-15x^5+12x^4-9x^3+9x^2
c: \(=3x\cdot5x^2-3x\cdot2x-3x=15x^3-6x^2-3x\)
d: \(=\dfrac{1}{2}x^2y\cdot2x^3-\dfrac{1}{2}x^2y\cdot\dfrac{2}{5}xy^2-\dfrac{1}{2}x^2y=x^5y-\dfrac{1}{5}x^3y^3-\dfrac{1}{2}x^2y\)
Thực hiện phép tính
1) (x-y).(6x2-4y2+\(\dfrac{1}{2}\)xy)
2) (6x-1).(3+x)+(2x+5).(-3x)
1. \(\left(x-y\right)\left(6x^2-4y^2+\dfrac{1}{2}xy\right)\)
\(=6x^3-4xy^2+\dfrac{1}{2}x^2y-6x^2y+4y^3-\dfrac{1}{2}xy^2\)
\(=6x^3+4y^3-\dfrac{11}{2}x^2y-\dfrac{9}{2}xy^2\)
===========
2. \(\left(6x-1\right)\left(3+x\right)+\left(2x+5\right)\left(-3x\right)\)
\(=18x+6x^2-3-x-6x^2-15x\)
\(=2x-3\)
Chúc bạn học tốt!
Thực hiện phép tính
1) (x-y).(6x2-4y2+\(\dfrac{1}{2}\)xy)
2) (6x-1).(3+x)+(2x+5).(-3x)
`1)(x-y)(6x^2-4y^2+1/2xy)`
`=6x^3-4xy^2+1/2x^2y-6x^2y+4y^3-1/2xy^2`
`=6x^3-11/2x^2y-9/2xy^2+4y^3`
`2)(6x-1)(3+x)+(2x+5)(-3x)`
`=18+6x^2-x-3-6x^2-15x`
`=-15x+15`
1)\(\left(x-y\right)\left(6x^2-4y^2+\dfrac{1}{2}xy\right)=6x^3+4y^3-\dfrac{9}{2}xy^2-\dfrac{11}{2}x^2y\)
2)\(\left(6x-1\right)\left(3+x\right)+\left(2x+5\right)\left(-3x\right)=\left(6x^2+17x-3\right)+\left(-6x^2-15x\right)=2x-3\)
tick mik nha
2: Ta có: \(\left(6x-1\right)\left(x+3\right)+\left(-3x\right)\left(2x+5\right)\)
\(=6x^2+18x-x-3-6x^2-15x\)
\(=2x-3\)