MATLAB基础教程习题答案作者杨德平习题答案课件.pdf

《MATLAB 基础教程》思考与练习答案? 第2 章? 1.?A=[2?6;‐1?5];?B=[1?‐3;2?7];? （1）?A+B?=? ???????????3????3? ??????? 1???? 12? （2 ）?5*A=? ? ????????? 10????30? ?????‐5????25? （3 ）?A*B?=? ????????? 14????36? ??????????9????38? （4 ）?A.*B?=? ??????????2???‐18? ??????‐2????35? （5 ）?A\B?=? ?????????‐0.4375???‐3.5625? ??????????0.3125????0.6875? （6 ）?A/B?=? ??????????0.1538????0.9231? ?????????‐1.3077????0.1538? （7 ）?A./B?=? ?????????2.0000???‐2.0000? ????????‐0.5000????0.7143? （8 ）?A.^B?=? ?????????? 1.0e+004?*? ??????????????0.0002????0.0000? ??????????0.0001????7.8125? 2.?A=[8?1?6;3?5?7;?4?9?2];? det(A)=?‐360；? ? inv(A)=? ??????0.1472???‐0.1444????0.0639? ??????‐0.0611????0.0222????0.1056? ???????‐0.0194????0.1889???‐0.1028? ? [V,D]=eig(A)? ?????V?=? ???????‐0.5774???‐0.8131???‐0.3416? ???????‐0.5774????0.4714???‐0.4714? ???????‐0.5774????0.3416????0.8131? ? ? ?? D?=? ???????? 15.0000?????????0?????????0? ??????????????0????4.8990?????????0? ??????????????0?????????0???‐4.8990? 3. （1）? A=[3 2 6;3 5 9;6 4 15]; b=[6 9 6]'; r1=rank(A) r2=rank([A b]) format rat if r1==r2&r1==3 x=A\b elseif r1==r2&r1<3 x0=A\b Z=null(A, 'r') else x= '无解' end 运行结果：? x?=? ???????4???????? ???????3???????? ??????‐2? （2 ）? A=[1 -2 3 -1;3 -1 5 -3;2 1 2 -2]; b=[1 2 3]'; r1=rank(A) r2=rank([A b]) format rat if r1==r2&r1==4 x=A\b elseif r1==r2&r1<4 x0=A\b Z=null(A, 'r') else x= '无解' end 运行结果：? x?=? ??无解? ? 第3 章? 3.?? S='matlab?programming?for?engineers'? findstr(S,'g')? 运行结果：? S?=? matlab?programming?for?engineers? ans?=? 11???? 18????26? ? 4.? C=cell(2,2); a={'Sun Yang','Liu Wen'}; b=char( '2012001','2012002'); c=[85 89 90;80 87 88]; d{1,1}='Maths'; d{1,2}='English'; d{1,3}='Matlab'; C{1,1}=a; C{1,2}=