Question

разложите на множители 1)81-(x^2+6x)^2, 1)c^2+4c+4-k^2, 3)a^2-b^2-10b-25.

Answer 1

1) 81-(x^2+6x)^2=(9-x^2-6x)(9+x^2+6x)
2) c^2+4c+4-k^2=(c+2)^2-k^2=(c+2-k)(c+2+k)
3) a^2-b^2-10b-25=a^2-(b^2+10b+25)=a^2-(b+5)^2=(a-b-5)(a+b+5)