2021-2022学年江西省余干初中数学毕业考试模拟冲刺卷含解析及点睛

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2V45x4=180,30x6=180,.,.180x80+180xl20=180x
80+120=36000FᐗG>AHIᢇ<Jᐳ6=ᑭ36000ᐗ.

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171VB(2,5),C(5,1).khBCḄ᪆iWy=-x+l.113ᵫEᙠkhBCᑣBE(m,=-----m+1.),F(m,-----m'+—m+1.)2221,3,1ஹ1,...FE="-mH—m+1-(--n+1)="-inl+lin.22221ᵫSACBF='EF»OB,2•"•SACBF='(—-m,+lm)x2=-m^Zm.22p..11,3ஹ5`♦SACDB=—BD»OC=-x(2-1)xl=—2222._.5•«SopCDBF=SACBF+SACDB=-m'+2m+—.2..........13ᓄW⚔Li0Sna®cDBF=-(m-1),+—.213m=lSopCDBFᨬᜧW2ELᙶ᪗W(1,1).(3)Rᙠ.2

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