2020-2021学年上学期高一期中数学试题及答案

5A{x|0x2}B{x|x，B（()RRA）A．{x|0xC．{x|1x2}B．{x|0xD．{x|0x2}B{x|x，RA(B){0xRB1f(x))()fx）4114(x)xa)2a2a，f4f(x)x2(,0)(0,)f(x)x(0,)，2(0,)(x)(m2m1)xf22m1在m122或）0B．1f(x)221102或m，mmm1f(x)(0,)在2m10m2，m，2）(2,1)(1,2)10x21x2(1,2)．xx202(ax2a,x2f(x)在a）Rlogx,x2a22(0,1))(0,][,1)22(ax2a,x2f(x)x2在Rlogx,a10a20a1则a122(a1)2alog2a）y2x与y2xxy()y|x|x与32x2f(x)x与g(x)fx()x与221xg(x)x1x1x2x(y2x与y，32x2xxx2x且yA32(x)2的定义域为)y|x|R，yBx2f(x)xRg(x)的定义域为{x|x，xC22(x)2x1的定义域为[,)(,]，f222g(x)x1x1的定义域为)Df(x)|x|g(x)x22()()fxgx，）2f(x)g(x)与f(x)g(x)x(x)g(x)f2a3b，m2ab）mm67C．12D．182a3b2m3，，ma，bmmm2abmmm)m232aba2b2f(x)(x4xmm2m12）4444[,3][,2)[,)[,2]3333x4x50x4x502，21x5(x24x5uloguy12(x)(x4xf，212(x)(x4xmmf212m2243m2m2m252，m4[,2)m323,02x1xf(x)(a)4fa）1logx,x0211111或28282342a11a4f(a)4或2，0a0a121aa18a0a0或，a8f(x)f(xf(x)f，(x)21x，R）11(6)f(7)f()11f(6)f()f(7)f221111(7)f()f(6)f()f(6)f(7)f22f(xf(x)f(xf(x)，(x)4f(x)f(x)f(x)，ffff0f(f(8f(1)1，，f113311f()f(4)f()f()f()21，2222211(6)f()f(7)f21(x)(xa)x,x(,)f221123f(x)f(x)02xx1a）211[]21[)2[1,)(,f(x)f(x)10()()(,)21以fxx2a在xx2132112在xaloguxa,令u2yu2131uxa0(,)且2在2a12211a112（2（）aa02245(x)x2xf(f(x)(xt，x2t，2222tty0f(x)t则2，0tf(x)(．(x)x2(ax2(af2在．3a(x)x2(ax2(f2在x(a1)4a3a，3．f(2）f0fx2x,2f(x)，x2f(1)0fx)0fx)f(1)x1x00x，∵fx)0．f(x)(1,aa)y(在)a30ax)300a3，aa10a1且，a3tyta1，a3,，3aa)．6A{x|x3x2}B{xx，或，C{x|m1x2}．()BRAB，；BCCm5AB{x|2x5}，()B{x|3x(,1)(2,)．2RAB{x|2x5}，A{x|3x()B{x|3x，．RRBCCCB．m1mm1；CC12mm5211m2m，2m55(,1)(2,)m．231(2)2(2)020.50.5；541x13xx12x22x2x221．5191121161()1()11．22441004310151x1311xx(xx)27x12，2222xx27211x2x2(xx1)222．x2x224725fxf(x)0ln3x2为Rx．yf(x))在f(x)f(xfx)xx023f(x){x|xx2}．或3xx0xx0，213x2f(x)f(x)ln(3x2)ln(3x2)ln则2，3x2212113x23x2xx01ln0fx，fx223x23x2212111yf(x))在∴x0x0，f(x)f(x)f(x)3x，由为Rxx03xx0f(x)∴．f(x)fx2|)f2x，而为Ryf(x))在2323∴|x2||2x|x或2xx{|x2}．或x(x)4k2kx[0,1]．，fk1xx1f(x)1(x)fk43．4k1(x)421在[0,1]fxx1f(x)f2f(x)f7，，故f(x)的值域为．(x))2k2k，2ttf，x2xxt)t2ktk．g21434k1gt()g(1)1kgt在k；min11②当1k2()()0，gxgkkkkk2244min1k2t)在12gx()gk(2)43kg，4min54k3k．4f(x)(x2．12f(x)Raf(3f(x)(x),2afa在()3a3a(x)(xR，f2122304a2120，∴x2aa．33f(32．a(x)(x4x则f2，122430由xxx1x3或．(x)x4x32，设m2x(x)()在∴f(x)()在(x)(x()23，f2nxx212(,a)(a,),2f(x)∵在724a30a2a∴a且，且4f(x)(在ang(x)f(x)yg(x)g(3)8Rm2g(x)yg(x)yf(x)，tf(2t3)f(tk)0k12xg(x)2()，fx9．kx22x1g(x)g(x)a0a1且a（xg82a()2，由a38gxxn2x(x)f．m2x1n1f(x)0，n，1Rfm212x(x)f．m2x112x12x0，f(x)f(x)0m2xm2x1112xm2)02()fx即2m．x22x112x12(x)f(x)Rf22x1221xt[1,4]f(2t3)f(tk)0f(2tf(kt)，f(2t3)f(tk)t3ktkt3，即tt3[0,9]k9．f(3f(x)(x),2afa在()3a3a(x)(xR，f2122304a2120，∴x2aa．33f(32．a(x)(x4x则f2，122430由xxx1x3或．(x)x4x32，设m2x(x)()在∴f(x)()在(x)(x()23，f2nxx212(,a)(a,),2f(x)∵在724a30a2a∴a且，且4f(x)(在ang(x)f(x)yg(x)g(3)8Rm2g(x)yg(x)yf(x)，tf(2t3)f(tk)0k12xg(x)2()，fx9．kx22x1g(x)g(x)a0a1且a（xg82a()2，由a38gxxn2x(x)f．m2x1n1f(x