全国2019版中考数学复习提分专练一实数混合运算与代数式的化简求值试题.docx

教学资料范本全国2019版中考数学复习提分专练一实数混合运算与代数式的化简求值试题编 辑：_时 间：_提分专练(一)实数混合运算与代数式的化简求值|类型1|实数的混合运算1.20xx成都 计算:2-2+38-2sin60+|-3|.2.20xx南充 计算:(1-2)2-1-220+sin45+12-1.3.20xx长沙改编 计算:|-3|+(-20xx)0-2sin30+13-1.4.20xx德阳 计算:(-3)2+12-3-(32)0-4cos30+63.|类型2|整式的化简求值5.20xx无锡 计算:(x+1)2-(x2-x).6.20xx江西 计算:(a+1)(a-1)-(a-2)2.7.20xx衡阳 先化简,再求值:(x+2)(x-2)+x(1-x),其中x=-1.|类型3|分式的化简求值8.20xx聊城 先化简,再求值:aa+1-a-1aaa+2-1a2+2a,其中a=-12.9.20xx株洲 先化简,再求值:x2+2x+1y1-1x+1-x2y,其中x=2,y=2.10.20xx眉山 先化简,再求值:x-1x-x-2x+12x2-xx2+2x+1,其中x满足x2-2x-2=0.11.20xx达州 化简代数式:3xx-1-xx+1xx2-1,再从不等式组x-2(x-1)1,6x+103x+1的解集中取一个合适的整数值代入,求出代数式的值.|类型4|与二次根式有关的计算12.20xx湖州 计算:2(1-2)+8.13.20xx陕西 计算:(-3)(-6)+|2-1|+(5-2)0.14.20xx恩施州 先化简,再求值:1x2+2x+11+3x-1x+2x2-1,其中x=25-1.15.20xx凉山州 先化简,再求值:1-a2+4ab+4b2a2-aba+2ba-b,其中a,b满足(a-2)2+b+1=0.参考答案1.解:2-2+38-2sin60+|-3|=14+2-232+3=94.2.解:原式=2-1-1+22+2=322.3.解:原式=3+1-1+3=6.4.解:原式=3+8-1-432+23=3+8-1-23+23=10.5.解:(x+1)2-(x2-x)=x2+2x+1-x2+x=3x+1.6.解:原式=a2-12-(a-2)2=a2-1-(a2-4a+4)=a2-1-a2+4a-4=4a-5.7.解:原式=x2-4+x-x2=x-4.当x=-1时,原式=-1-4=-5.8.解:aa+1-a-1aaa+2-1a2+2a=aa+1-a-1aaa+2-1a(a+2)=aa+1-a-1aa2a(a+2)-1a(a+2)=aa+1-a-1aa2-1a(a+2)=aa+1-a-1aa(a+2)a2-1=aa+1-a-1aa(a+2)(a+1)(a-1)=aa+1-a+2a+1=a-(a+2)a+1=a-a-2a+1=-2a+1,当a=-12时,原式=-2-12+1=-212=-212=-22=-4.9.解:x2+2x+1y1-1x+1-x2y=(x+1)2yx+1-1x+1-x2y=(x+1)2yxx+1-x2y=x(x+1)y-x2y=x2+xy-x2y=x2+x-x2y=xy.当x=2,y=2时,原式=2.10.解:原式=(x-1)(x+1)-x(x-2)x(x+1)(x+1)2x(2x-1)=2x-1x(x+1)(x+1)2x(2x-1)=x+1x2.由题意得:x2=2x+2,代入得:原式=x+12x+2=12.11.解:解不等式,得x1,解不等式,得x-3,不等式组的解集为-3x1.3xx-1-xx+1xx2-1=3x(x+1)-x(x-1)(x-1)(x+1)x2-1x=3x(x+1)-x(x-1)(x-1)(x+1)(x-1)(x+1)x=3(x+1)-(x-1)=3x+3-x+1=2x+4.x0,x1,当x取-2时,原式=2(-2)+4=0.12.解:原式=2-22+22=2.13.解:(-3)(-6)+|2-1|+(5-2)0=18+2-1+1=32+2=42.14.解:1x2+2x+11+3x-1x+2x2-1=1(x+1)2x+2x-1(x+1)(x-1)x+2=1x+1.当x=25-1时,原式=125-1+1=510.15.解:1-a2+4ab+4b2a2-aba+2ba-b=1-(a+2b)2a(a-b)a-ba