1.若a-b=5,ab=2,则（a+b）^2=

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1.（a+b）^2=（a-b）^2+4ab=33
2.a^2+3ab+b^2=（a+b）^2+ab=35
3.2;5;7;15;6;
(1).(2x+1)^2-(2x-1)^2=8x;
(2).(2x+1)^2-(2x-1)^2
=[(2x+1)+(2x-1)]*[(2x+1)-(2x-1)]
=4x*2=8x4.c(a-b)^2=(a+b)^2-4ab=8
5.(2013-a)-(2011-a)=4024；
(2013-a)^2+(2011-a)^2
=[(2013-a)+(2011-a)]^2-2(2013-a)*(2011-a)
=4024-2×1005
=20146.(3+1)(3^2+1)(3^4+1)·...·(3^32+1)/2-3^64/2
=(3-1)(3+1)(3^2+1)(3^4+1)·...·(3^32+1)/2-3^64
=(3^2-1)(3^4+1)·...·(3^32+1)/2-3^64/2
=(3^64-1)/2-3^64/2
=-1/2