a: =x^2+6x+9+x^2-6x+9+2x^2-32
=4x^2-14
b: =(x+3-10+x)^2=(2x-7)^2=4x^2-28x+49
c: =(x-3-x+5)^2=2^2=4
e: =x^2+10x+25-x^2+10x-25=20x
d: A=(5-1)(5+1)(5^2+1)(5^4+1)/4
=(5^2-1)(5^2+1)(5^4+1)/4
=(5^4-1)(5^4+1)/4
=(5^8-1)/4
g: =x^2-9-x^2-4x+5
=-4x-4
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