七年级数学下册第一章整式的乘除6完全平方公式第1课时完全平方公式的认识练习1新版北师大版.docx

完全平方公式的认识一、选择题1.2x-12等于A4x2-4x+1 B2x2-2x+1 C2x2-1 D2x2+1 2.x+5y2等于Ax2-5y2 Bx2+10x+25y2 Cx2+10xy+25y2 Dx2+x+25y2 3.m-52 等于Am2-5 Bm2-52 Cm2-10m+25 D25m2-54.x+5y2 等于Ax2-5y2 Bx2-10y+5y2 Cx2+10xy+25y2 Dx2-y+25y2 5.2x-y2 2 等于A2x2-4xy2+y4 B4x2-2xy2+y4 C4x2-4xy2+y4 D4x2-xy2+y4 6.下面计算正确的选项是A.(a+b)(a-b)=2a+2b B.b5+b5 =b10 C.x5 .x5= x25 D.(y-z)2=y2-2yz+z27.下面计算错误的选项是A.(y-z).(y+z)=y2-z2 B.(m-n)2=n2-m2 C.(y+z)2=y2+2yz+z2 D.(y-z)2=y2-2yz+z28.(2y-3z)2 等于A. 4y2-12yz+z2 B.y2-12yz+9z2 C.4y2-12yz+9z2 D.4y2-6yz+9z2 9 (3z-y)2 等于A.9z2-y+y2 B.9z2-yz+y2 C. 9z2-6yz+y2 D3z2-6yz+y2 10 (x+3ab)2 等于A.x2+6xab+9a2b2 B.x2+6ab+9a2b2 C.x2+xab+9a2b2 Dx2+6xab+a2b2 11 (c-a2b2)2等于A .c-ab2 B.c2-2a2b2c+a4b4 C.c-a2b2c+a4b4 Dc2-2abc+a4b12 c-a2)22等于A.c-a2 B.c2 -2a4c+a8 C.c2 -a2 Dc2-a413. c2)2+a2)22等于A .c8+2ac4+a8 B.c8+2a4c+a8 C.c8+2a4c4+a8 Dc8+a4c4+a8 14.c+a)2等于A.c3 -a3 B.a2+2ac+c2 C.c5-a5 Dc2-2ac+a215.d+f2等于A .d3-f3 B.d2+2df+f 2 C.d2-2f+f 2 Dd2-df+f 2 二. 填空题.15-x22等于；2x-2y2等于；3.3a-4b2等于；4.2b-2c2等于；三、计算题1.3a-b3a+b-a+b22.a-b2 -3a2+b23.2a2+b2-a+b24.3a-b3a+b-2a-b2答案：一、选择题1.A2.C3.C4.C5.C6.D7.B8.C9.C10.A11 .B12.B13. C14.B15.B二、填空题.125-10x2+x42x2-8xy+4y23.9a2-24ab+16b24.4b2-8bc+4c2三、计算题1.解：3a-b3a+b-a+b2=9a2-b2-a2-b2-2ab=8a2-2b2-2ab2.解：a-b2-a2+b2=a2-2ab+b2-3a2-3b2=-2a2-2ab-2b23.解：a-ba+b-a2+b2=2a2-2b2-a2-2ab-b2=a2-2ab+b24.解：3a-b3a+b-2a-b2=9a2-b2-4a2+4ab-b2=5a2+4ab-2b2