( 3√2 + 2√3 ) ² - ( 3√2 + 2√3 ) · ( 3√2 - 2√3 )==9·2 + 2·3√2·2√3 + 4·3 - ((3√2)²-(2√3)²)=18 + 12√6 + 12 -18 +12=12√6 + 24=12(√6+2)
A²-14a+49=a²-2*7+7²=(a-7)²
x²+8x+16=x²+2*4x+4²=(x+4)²
a(a+2b)-(b+a)²=a²+2ab-(b²+2ab+a²)=a²+2ab-b²-2ab-a²=-b²
3(b-1)²+8b=3(b²-2b+1)+8b=3b²-6b+3+8b=3b²+2b+3
2c(8c-3)-(4c+1)²=16c²-6c-(16c²-2*4c*1+1)=16c²-6c-16c²+8c-1=2c-1