2021年电大工程数学形成性考核册答案

工程数学作业（一）答案第2章2aaaaaa1bbb2312322ab2ab2abD12ccc3112233ccc1231234466000100a00200100a1aA111122110cC2452123178A,BnABAB111(AB)BA11B)AB(AB)AB(A1111110k1且DA,BnkBABABnABAkAkA(k)AkAn若AA1若A,Bn若A,Bn0若A,BnAB1211325255532121ABA0A0*0A*0A,B,Cn(ACB)D1BCA(B)AC11111(B1)C1A1A1C(B1)1A,B,CnAB)A2ABB(AB)BBAB(A22222CBA(2ABC)2CBA(2ABC)1111221040⒈17．0011111111xx2⒉1．4B25为ACBC为A为341515A．0101121200640,B(AB)A31451834B32ABA,B3A．1,B3AB)A,B3A1a3．12aA0．012124022．033AO1A1OA,A1．1OA1OA21228121,C54,BABAC2AC；A35435B(AB)C．⑷A06616ABAC2AC1804372277A5B(AB)C0114121103,B,C321．A012210021140246410ACBC(ABC3021221020102310102121,B1113A2XBX中．A3422112XB3A3418321251XAB)252112227115711522241020143602533110a,a4142020120(4360(13645aa4142414225305312341000122231211002⑴21；⑵；⑶．1111110122110261111解：（1）1322100100102121221023rr312rr212rr1203621003622rrA|I22010013231001320121220600921323122901r10221009291312212r2rrr2r01031010933232329990011001221999999122929192A192929199922626171000002017511）()A1A11021001101530114101101110110010121012113201解：10110110110111011011rr0110110110111101100rr1213242rrrr141000011101012101000110111220001110211320110110110110111rr3400011100000000R()34AAA(A')''(')''AA'AAA是IA1或1．nA是AAInAA2I11A或1AAAAAA1(A)(A)A(A)111即A工程数学作业（第二次）)第3章2)241xxxx1123xx0解xC232x2x332][7,2,2]0,[11,2,2][11,2,2]232xxx123x6xB133x3x42310,1,0,2,000114324501001,,,B011112340101,,,,,121231241⒌与AA(A)秩()秩(A)(A)秩秩秩(A)秩(A)秩()(A)1秩ADA,,,21s9阶矩阵，nx是是是是BxnABBA(AB)PAP1BB2)x0x１x12x0121,1,10,0,0,．121,2,3,1,2,0,1,0,0,0,0,0３．xxx00112233123,,．1230,1,0,01,0,．,12312,,,,,,秩．12s12sb05(A)3２bX0X,X201．XkX1kX0122IA0AA1第19)13x2xx6x12343x8xx5x012342xx4xx1234x4xx3x21234解：1019231321613216013rr3rr0173815078818125r21r2rrA1323rrrr1241148101421050027399014132013480010122610101003rr19rr430178101787rr310101rr322345rr4330033001140056001140056000100124x21041101r1x4142001x1300013x3411x11y1z112?A1111111122rr11120111rrrr21313011131111122］211)011rr23(2))002当且R()R(A)312当R()R(A)11,,123837253756,,,31012310321,,x11xx331232223581030137756341A,,,1171231037001000032110571R(A)R(),,1231131173962,8,0,12343933641331311131117390112280600018,,,1234393300000000413363xx2x0x12345xx2x3x01234xx2x5x0122343x5x4x0145113121312103rr5rr1414327142151230143712rrrr0A13233rrrr1121414324150700000035040143100351515101010012r31r231313rrrr3r30010120132341402314021140000000100000000000055xx14114333xx令x1142140330x415x2x3xx12343xx4x2x51234x9x4x1245x3x6xx11234解：97121523111523111510rr3142rr1421014272812rrrr7280142A134235rr2rr41714728219001420000061028414565300000971210171x1xx1111324r92011472011xxx200002732400000令，，xkxkkk31421271712kk11x9122911x1112kk2kk2027270x121213kx0412k01a,a,a,a31241110111，，，10203141000110000100102103214300001100a01a0100a1a()a()a()aaaa240a10203112213324433a00014(aa)(aa)(aa)a12123234344AXBnR(A)R()nAXBR()n0R()nAXB019是可逆矩阵Ａ特性值，且0A1AIA(A)A()A(AA)11111A11即A1fxxxx2xx2xx2xx2xx2122232412242334f(xx)xx2xx2xx2xx(xx)x2xxx)x2xx2222221234242334123324424(xx)(xxx)x222212324令yxx，yxxx，yx，xy11223243244xyy113yx即23xyyy3234xy44fyyy212223工程数学作业（第三次）)第4章⒈A,BB)BAB)BA(AB)BA(AB)BA(A(AA与BUABABU且A与B3131D3C3222A,BCA,BA,BBABAA,BA,BA,BA,B31Dp(0pp)1pp)p)3pp)pp)3322,D(X)X~B(n,p)E(X)与Anp8b)E(X)，设f(x)Xa,b(aA(x)dxb(x)dxabf(xxf(x)dxaBsinx,xsinx,0xf(x)f(x)2220,其它0,其它sinx,0xsinx,0xf(x)2f(x)0,其它0,其它9.Xf(x)F(x)(a,b)Xb)（P(aF(a)f(a)Fb)fb)bF(xxf(x)dxabaEY)0,DY)1,D(X)设XE(X)C．2YXXYYXXY223．5,P(B)A,BP(AB)2.P()P(AB)，．P(AB)PAAA,BB．P(AB),P(A)pP(B)1P．P(AB)p,P(B)qP(AB)pq．A,BP(),P(B)A,BP(AB)P()，P(AB)．0x0X~U(0,XF(x)01．xx1x1若X~B(20,E(X)6．3)若X~N(,)P(X2．2E[(XE(X))(YEY))](X,Y)．设A,B,CA,B,C⑴A,B,C⑵A,B,C⑶A,B,C⑷A,B,C⑸A,B,C⑹A,B,CC解ABCABCABCABCABCABCABCABCABCABC322⑴2⑵21解设221ABCC12CCC63923C2231312C23P()P(B)52255i）AiP(AA)P(A)P(A|A)12121""A"A""A"213B""P(B)P(A)P(B|A)P(A)P(B|A)P(A)P(B|A)112233XpP(XPP(X2)P)PP(XP)P2P(Xk)P)Pk1故X123kpp)pp)pp)p2k1X012345604),P(2XP(XP(X．(X(X(X(X(X(XP(2XP(X2)P(XP(X4)P(X0.20.30.120.10.72P(X1P(X10.30.7Xx12x,0f(x)0,其它11),P(X2)P(X．2421212121142xP(X)f(x)2002111521P(X2)f(x)dx2xdxx116411444x12x,0E(X),D(X)．设X~f(x)0,其它131022E(X)x2xdxxf(x)dxx330224102121E(X)xf(x)dxx2xdxx240121D(X)E(X)[E(x)]()2222318X)P(X．设~2)P(XNX1XX1121P(X0)P(1.67)110.95250.04750.6，设2,D(X)设X,X,,X是独立同分布随机变量，已知E(X)