2020考研数学一真题【完整版】

120201~8432..1.0xA.201xtedtB.30ln(1)xtdtC.sin20sinxtdtD.1cos20sinxtdt2.()fx-110lim()0,xfxA.0()lim0,()0||xfxfxxx.B.20()lim0,()0xfxfxxx.C.0()()0lim0.||xfxfxxxD.20()()0lim0.xfxfxxx3.()fx00(0,0)(0,0)0,,,1fffnxydnA.22(,)(0,0)|(,,(,))|lim0xynxyfxyxyB.22(,)(0,0)|(,,(,))|lim0xynxyfxyxyC.22(,)(0,0)|(,,(,))|lim0xydxyfxyxyD.22(,)(0,0)|(,,(,))|lim0xydxyfxyxy24.R1nnnaxrA.1nnnax||rRB.1nnnax||rRC.||rR1nnnaxD.||rR1nnnax5.ABA.PPA=BB.PBP=AC.PPB=AD.Ax=0Bx=06.22211112:xaybcLabc33322222:xaybcLabc,1,2,3.iiiiaabicA.1a23,aaB.2a13,aaC.3a12,aaD.123,,aaa7.A,B,C11()()(),()0()()412PAPBPCPABPACPBCA,B,CA.34B.23C.123D.5128.12(),,,nxxxX1(0)(1),()2PXPXx100155iiPXA.1(1)B.(1)C.1(0,2)D.(0,2)914224.9.011lim1ln(1)xxex10.221ln(1)xtytt212|tdydx11.()fx()()()0(0),(0),(0)fxafxfxafmfn0()dfxx12.20(,)edxyxtfxyt2(1,11)fxy13.011011110110aaaa14.x,22sinYX(,CovXY15~2394...415.1033(,)8fxyxyxy16.10222444LxyxyIdxdyxyxyL22xy17.10{}na111(1)12nnaxana||1x1nnnax.18.102222:4Zxyxy()fx[()2][()2][2()2]Ixfxyydydzyfxyyxdzdxfxydxdy19.()fx[0,2](0,2)(0)(2)0,max{|()|},xffMfx1(0,2)|()|fM2(0,2),|()|xfxM0M.20.22121122(,)44fxxxxxx1122xyQxy22121122(,)4gyyayyybyab.1,ab.2Q.21.A2(,)PAA.1P2260AA1PAPA.22.X1X2X3X1X2X33331321{0}{1},(1)2PXPXYXXXX.1X1Y()x.2Y.23.T51e,0,()0,.mttFtm,.1{}PTt{|}PTStTS0,0St.2n12,,ntttm?.