(2x+3)² -(2x-3)(2x+3)+2(x-1)² =
=(2x+3)(2x+3 -2x+3)+2(x²-2x+1) =
=6(2x+3)+2x²-4x+2 =
=12x+18+2x²-4x+2 =
=2x²-8x+20 =
=2(x²-4x+10)
(3√2+2√3)²+2(√3-√2)²-(√7+√5)(√7-√5)=
= 18+12√6+12+2(3-2√6+2)-(7-5)=
= 30+12√6+2(5-2√6)-2=
= 30+12√6+10-4√6-2=
= 38+8√6=
=2(19+4√6)
