1

1)(8y-x)(8y+x)

2)(ab^2-9)(ab^2+9)

3)(5nm^2-3a^4)(5nm^2+3a^4)

2

1)k^2-2k+1

2)64+16m+n^2

3

1)4a^2+20ab+25b^2

2)1/9x^2+1/2xy+9/16y^2

3)0,16x^2-4xy+25y^2

4)n^4-6m^3n^2+9m^6

5)x^4y^2+2x^4y^4+y^6