81(2k+1)2-(k-3)2
81(2k+1)^2-(k-3)^2=(9(2k+1)-k+3)(9(2k+1)+k-3)==(18k+9-k+3)(18k+9+k-3)=(17k+12)(19k+6).
(8p-5)2-9(3p+2)2
((8p-5)-3(3p+2))(8p-5)+3(3p+2))==(8p-5-9p-6)(8p-5+9p+6)=-(p+11)(17p+1) .
81(2k+1)2-(k-3)2
81(2k+1)^2-(k-3)^2=(9(2k+1)-k+3)(9(2k+1)+k-3)=
=(18k+9-k+3)(18k+9+k-3)=(17k+12)(19k+6).
(8p-5)2-9(3p+2)2
((8p-5)-3(3p+2))(8p-5)+3(3p+2))=
=(8p-5-9p-6)(8p-5+9p+6)=-(p+11)(17p+1) .