bài 2
a)
\(=3\left(x-y\right)+5x\left(x-y\right)\)
\(=\left(3+5x\right)\left(x-y\right)\)
c)
\(=x\left(x-1\right)+y\left(x-1\right)=\left(x+y\right)\left(x-1\right)\)
d)
\(=7x\left(5x-y\right)+2\left(5x-y\right)+3y\left(5x-y\right)\)
\(=\left(7x+2+3y\right)\left(5x-y\right)\)
e)
=\(2y\left(3-x\right)-3xy\left(3-x\right)=\left(2-3x\right)\left[y\left(3-x\right)\right]\)
bài 1
a) = x(5x-6)
b) = 3x(y+4x)
c)=6x2(4x+1)
d)=\(2ab\left(a-2\right)\)
e)\(=\left(x-5y\right)\left(x+y\right)\)
f) \(\left(x-y\right)\left(y+2\right)\)
Bài 2:
a: \(3\left(x-y\right)-5x\left(y-x\right)\)
\(=3\left(x-y\right)+5x\left(x-y\right)\)
\(=\left(x-y\right)\left(5x+3\right)\)
b: \(\dfrac{2}{5}x\left(y-1\right)+\dfrac{2}{5}y\left(1-y\right)\)
\(=\dfrac{2}{5}x\left(y-1\right)-\dfrac{2}{5}y\left(y-1\right)\)
\(=\dfrac{2}{5}\left(y-1\right)\left(x-y\right)\)
c: \(24x^3+6x^2\)
\(=6x^2\left(4x+1\right)\)
d: \(7x\left(5x-y\right)+2\left(5x-y\right)-3y\left(y-5x\right)\)
\(=\left(5x-y\right)\left(7x+2\right)+3y\left(5x-y\right)\)
\(=\left(5x-y\right)\left(7x+3y+2\right)\)
bài 3
a)
=x(x-y)-y(x-y)
=(x-y)(x-y)
=(x-y)2
thay x=53 y=3 ta có
(53-3)2=502=2500
b)
=(x2-4x+4)(x-1)
=(x-2)2(x-1)
thay x=3 ta có
(3-2)2(3-1)
=1.2=2
c)
=x(2x-y)+z(2x-y)
=(x+z)(2x-y)
=(1,2+1,8)(2.1,2-1,4)
=3.1=3
mọi người giúp mik với ạ mik đang cần gấp ( nếu xong trg 45 phút thì càng tốt ) cảm ơn mọi người :'))
