有4條數唔識...

1.xy+bx+ay+ab
=x(b+y)+a(b+y)
=(b+y)(a+x)

2.mp-np+mq-nq
=p(m-n)+q(m-n)
=(m-n)(p+q)

3.ux+2vx+u+2v
=x(u+2v)+(u+2v)
=(u+2v)(x+1)

4.mr+5m-nr-5n
=m(5+r)-n(5+r)
=(5+r)(m-n)

1.
xy+bx+ay+ab
=x(y+b)+a(y+b)
=(x+a)(y+b)

xy+bx+ay+ab
=xy+ay+bx+ab
=y(x+a)+b(x+a)
=(y+b)(x+a)

2.mp-np+mq-nq
=p(m-n)+q(m-n)
=(p+q)(m-n)

3.ux+2vx+u+2v
=ux+u+2vx+2v
=u(x+1)+2v(x+1)
=(u+2v)(x+1)

4.mr+5m-nr-5n
=mr-nr+5m-5n
=r(m-n)+5(m-n)
=(r+5)(m-n)

xy+bx+ay+ab
= x(y+b)+a(y+b)
= (x+a)(y+b)

mp-np+mq-nq
= p(m-n)+q(m-n)
= (p+q)(m-n)

ux+2vx+u+2v
= ux+u+2vx+2v
= u(x+1)+2v(x+1)
= (u+2v)(X+1)

mr+5m-nr-5n
= m(r+5)-n(r+5)
= (m-n)(r+5)

1)x(y+b)+a(y+b)
=(x+a)(y+b)

2) m(p+q)-n(p+q)
=(m-n)(p+q)

3) u(x+1)+2v(x+1)
=(u+2v)(x+1)

4)r(m-n)+5(m-n)
=(r+5)(m-n)