1)4/9p²q²-1
=(2/3pq-1)(2/3pq+1)
(2)25(m+n)²-9n²
=[2(m+n)+3n][2(m+n)-3n]
=(2m+2n+3n)(2m+2n-3n)
=(2m+5n)(2m-n)
(3)4a³-4a²+a
=a(4a²-4a+1)
=a(2a-1)²
(4)(x-1)(x-3)+1
=x²-4x+3+1
=x²-4x+4
=(x-2)²
1)4/9p²q²-1
=(2/3pq-1)(2/3pq+1)
(2)25(m+n)²-9n²
=[2(m+n)+3n][2(m+n)-3n]
=(2m+2n+3n)(2m+2n-3n)
=(2m+5n)(2m-n)
(3)4a³-4a²+a
=a(4a²-4a+1)
=a(2a-1)²
(4)(x-1)(x-3)+1
=x²-4x+3+1
=x²-4x+4
=(x-2)²