完全平方公式 是…………………………( ) (A)8 (B)16 (C)32 (D)64 1.(a+2b)2=a2+ _______ +4b2. 17 .如果4a2-N·ab+81b2是一个完全平方式,则N2.(3a-5)=9a+25-_______. 223.(2x-______)2=____-4xy+y2. 24.(3m2+_______)=_______+12m2n+________. 等于……………………… ( ) (A)18 (B)±18 (C)±36 (D)±64 18.若(a+b)2=5,(a-b)2=3,则a2+b2与5.x2-xy+________=(x-______)2. 6.49a2-________+81b2=(________+9b)2. 7.(-2m-3n)2=_________. 8.(1s+1t243)2=_________. 9.4a2+4a+3=(2a+1)2+_______. 10.(a-b)2=(a+b)2-________. 11.a2+b2=(a+b)2-______=(a-b)2-__________. 12.(a-b+c)2=________________________. 13.(a-2b+3c-d)(a+2b-3c-d) =[(a-d)-(_____ )][(a-d)+(_____ )] =( )2-( )2. 14.(a2-1)2-(a2+1)2=([a2-1)+(a2+1)][(a2-1)-(______)]=__________. 15.代数式xy-x2-1y24等于……………………( ) (A)(x-1y)2 (B)(-x-1y)2 22(C)(1 12y-x)2(D)-(x-2y)2 16.已知x2(x2-16)+a=(x2-8)2,则a的值ab的值分别是………………( ) (A)8与12 (B)4与12 (C)1与4 19.计算下列各式 (1)(-2a+5b)2; (2)(-1222ab2-3c); (3)(x-3y-2)(x+3y-2); (4)(x-2y)(x2-4y2)(x+2y); D)4与1 ( (5)(2a+3)2+(3a-2)2; (6)(a-2b+3c-1)(a+2b-3c-1); (7)(s-2t)(-s-2t)-(s-2t)2; (8)(t-3)2(t+3)2(t 2+9)2. 20.用简便方法计算: (1)972; (2)20022; (3)992-98×100; (4)49×51-2499. 21.求值: (1)已知a+b=7,ab=10,求a2+b2,(a-b)2的值. (2)已知2a-b=5,ab=32,求4a2+b2-1的值. (3)已知(a+b)2=9,(a-b)2=5,求a2+b2,ab的值. 本文来源:https://www.wddqw.com/doc/77bc134f001ca300a6c30c22590102020740f2e4.html