习题一答案 1. 求下列复数的实部、虚部、模、幅角主值及共轭复数: (1)132i (2) (1)(2)iii (3)131iii (4)8214iii 解:(1)1323213izi, 因此:32Re, Im1313zz , 1232, argarctan, 3131313zzzi (2)3(1)(2)1 310iiiziii , 因此,31Re, Im1010zz , 1131, argarctan, 3101010zzzi (3)133335122iiiziii , 因此,35Re, Im32zz , 34535, argarctan, 232izzz (4)82141413ziiiiii 因此,Re1, Im3zz , 10, argarctan3, 1 3zzzi 2. 将下列复数化为三角表达式和指数表达式: (1)i (2) 13i (3) (sincos )ri (4) (cossin )ri (5)1cossin (02 )i 解:(1)2cossin22iiie (2)13i 23222(cossin)233iie (3)(sincos )ri()2[cos()sin()]22irire (4)(cossin )ri[cos()sin()]irire (5)21 cossin2sin2 sincos222ii 22sin[cossin]2sin2222iie 3. 求下列各式的值: (1)5( 3)i (2)100100(1)(1)ii (3)(13 )(cossin )(1)(cossin )iiii (4)23(cos5sin5 )(cos3sin3 )ii (5)3 i (6)1 i 解:(1)5( 3)i5[2(cos()sin())]66i 5552 (cos()sin())16( 3)66ii (2)100100(1)(1)ii50505051(2 )( 2 )2(2)2ii (3)(13 )(cossin )(1)(cossin )iiii 2[cos()sin()](cossin )332[cos()sin()][cos()sin()]44iiii 2[cos()sin()](cos2sin 2 )1212ii (2)122[cos(2)sin(2)]21212iie (4)23(cos5sin5 )(cos3sin3 )ii cos10sin10cos19sin19cos( 9 )sin( 9 )iii (5)3 i3 cossin22i 11cos (2)sin(2)3 23 2kik31 , 02231 , 122, 2ikikik...