b.10x(x-y)-6y(y-x)=10x(x-y)+6y(x-y)=(10x+6y)(x-y)
c.3x2+5y-3xy-5x=(3x2--3xy)-(5x-5y)=3x(x-y)-5(x-y)=(3x-5)(x-y)
a.3x2-6x+9x2
= 3x(x-2+3x)
b.10x(x-y)-6y(y-x)
= 10x(x-y)+6y(x-y)
=(10x+6y)(x-y)
c.3x2+5y-3xy-5x
=(3x2-3xy)+(5y-5x)
=3x(x-y)+5(y-x)
= 3x(x-y)-5(x-y)
=(3x-5)(x-y)
d.3y2-3z2+3x2+6xy
=3(y2-z2+x2+2xy)
= 3(x2+2xy+y2)-z2
=3(x+y)2-z2
=3(x+y-z)(x+y+z)
e.16x3+54y3
= 2(8x3+27y3)
=2(8x+27y)(8x2-8x.27y+27y2)
=2(8x+27y)(8x2-216xy+27y2)
f.x2-25-2xy+y2
= (x2-2xy+y2)-25
=(x-y)2-25
=(x-y-5)(x-y+5)
tớ ko làm đúng chính xác đâu nha
^-^
