5.80.

1) (a+b²)(a²-ab+b²)

2) (x³-y)(x6+x³y+y²) /x6 это х в степени 6/

3) (x²+y²)(x⁴-x²y²+y⁴)

4) (x²+y)(x⁴-x²y+y²)

5) (p-q³)(p²+pq³+q6)

6) (m-n)(m²+mn+n²)(m6+m³n³+n6)

5.81.

1) (m+n)(m²-mn+n²)

2) (x³-y²)(x6-x³y²+y⁴)

3) (a²-2)(a⁴+2a²+4)

4) (b³+3)(b6-3b³+9)

5.82.

1) (xy+1)(x²y²-xy+1)

2) (3-ab)(9+3ab+a²b²)

3) (a²c-b)(a⁴c²+a²bc+b²)

4) (1-xy)(1+xy+x²y²)

5) (ab+4)(a²b²-4ab+16)

6) (3x-yz)(9x²+3xyz+y²z²)