1. Using what we have learned, we can derive the following elegant equations: A? +b？ +c？ -ab-bc-ac=？ [﹙a-b﹚？ +﹙b-c﹚？ +﹙c-a﹚？ The transformation of the equation from left to right not only maintains the symmetry of the structure, but also embodies the harmony and simplicity of mathematics.

(1) Please verify the correctness of this equation;

When a= 1, b=0 and c=- 1.

Left = 1? +0? +(- 1)? - 1×0-[0×(- 1)]-[ 1×(- 1)]=3

Right =? [﹙ 1-0﹚? +﹙0-(- 1)﹚? +﹙(- 1)- 1﹚? ]=3

(2) If A = 2009, B = 20 10 and C = 20 1 1, can you find A quickly? +b？ +c？ -the value of ab-ba-AC?

Answer? +b？ +c？ -ab-ba-ac

=? [﹙2009-20 10﹚? +﹙20 10-20 1 1﹚? +﹙20 1 1-2009﹚? ]=3

2. Solve the equation: (x+3)(x-2)-(x+ 1)? =﹣ 1

(x+3)(x-2)=(x+ 1)？ ﹣ 1

(x+3)(x-2)=(x+ 1﹣ 1)(x+ 1+ 1)

(x+3)(x-2)=x(x+2)

x？ +x-6=x？ +2 times

x=-6