1)2=ex(ex-x-2)(ex-1)2.?L(x)=ex-x-2,L′(x)=ex-1>0~x∈(2,+∞)&?1,AL(x)=ex-x-2~x∈(2,+∞)WX??,AL(x)>L(2)=e2-4>0,@h′(x)>0,Ah(x)=xex+1ex-1~x∈(2,+∞)WX??,h(x)>h(2)=2e2+1e2-1.??,m≤2e2+1e2-1.(22)(Ⅰ)ì?BE,_∠BED=∠BAC.áIABI?OFk?,@BE⊥AC,_à∠DEC=90°-∠BED=90°-∠BAC=∠DCE,??DE=DC.\DB=DE,@DC=DB,AODj△ABCF($LMí,@OD∥AC.(Ⅱ)=>?,~Rt△OBDL,∠BOD=60°,_OD=2OB,@OMOD=OBOD=12.(23)(Ⅰ)ρ槡=22cos(θ+π4),Aρ2=2ρcosθ-2ρsinθ,Ax2+y2=2x-2y,Ax2+y2-2x+2y=0,@2íCFkl??1xI(x-1)2+(y+1)2=2.(Ⅱ)kílF3D1xIx=ty=3t+{a(tI3D),4Ikl??1x,A3x-y+a=0,￠?(2,3)56ZJa=-3,@kílFkl??1xI3x-y-3=0.?vCPkílFw3Id=1槡10=槡1010,@kíl7?C?JFu±I2r2-d槡2=槡1905.(24)(Ⅰ)áI|2x-1|+|2x+5|≥|(2x-1)-(2x+5)|=6,Af(x)≥6(x∈R),??f(x)-m≥0&?1/??6-m≥0,ù8jm≤6,fDmF?}??j(-∞,6].(Ⅱ)áIn=6,_|x-3|-2x≤4,A|x-3|≤4+2x.?x<3,_3-x≤4+2x,;Jx≥-13,A-13≤x<3;?x≥3,_x-3≤4+2x,;Jx≥-7,,*x≥3./?x≥-13.?/?|x-3|-2x≥2n-8F;?I[-13,+∞).
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