2021中考数学必刷题(二)

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23(2)|P}x~ḄᚖRACN.\R4cḄ᪆-Y>=ª+஻?ᵫ⚪¬3&+;=0,[m=—3[m=-3\RACḄ᪆-Yy=-x-3.Pᙶ᪗Y(x,x2+2x-3),ᑣNḄᙶ᪗Y(x,-x-3),PN=PE-NE=-(x2+2x—3)+(-x-3)=-x2-3x.S"AC~+S"CN':.S=-PNOA21,=—x3:-x2-3x3,27=--:XH--H---f228.•.ºx=-3»sᨵᨬᜧ2,d»pḄᙶ᪗Y:-3,--C2824(3)ᙠy~]2¿ᙠÀÁÂA4DM2\QoQG.ᳮᵫ᝞Åy=x2+2x—3=y=(x+l)2-4,⚔஺Ḅᙶ᪗Y(-1,-4),A(-3,O),AD2=(-l+3)2+M-O)2=2O.MḄᙶ᪗Y(O,f),ᑖo>IBজºAY\Q⚔»᝞M3জᵫlmkᳮAM2+AD2=DM2,ᓽ(0+3)2+Q—Of+20=(0+lÊ+(f+4)2,f=32ᡠMḄᙶ᪗Y(0,g)ঝº஺Y\Q⚔»᝞M3ঝᵫlmkᳮ,஺/+Í=4”,gp:12:2+20=:0+32+:/-02,0++z+4

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