x^4-16-(x+2)(x-2)(x^2+4)+2005=x^4-16-(x^2-4)(x^2+4)+2005=x^4-16-(x^4-16)+2005=x^4-16-x^4+16+2005=2005
（2+1)(2^2+1)(2^4+1)(2^8+1)(2^16+1) =(2-1)（2+1)(2^2+1)(2^4+1)(2^8+1)(2^16+1)=(2^2-1)(2^2+1)(2^4+1)(2^8+1)(2^16+1)=(2^4-1)(2^4+1)(2^8+1)(2^16+1)=.=2^32-1
(y+3x)(3x-y)-(3y-x)(3y+x)=9x^2-y^2-9y^2+x^2=10x^2-10y^2当x=-2,y=3时,原式=-50
(a+3)^2-(a-1)^2=(a+3+a-1)(a+3-a+1)=4（2a+2)=8a+8