[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fjCRBtUoCTdySSkgzJsc_19TuHhnPjh55mn2xXxMju_I":3},{"answer":4,"createTime":5,"id":6,"options":7,"origin":12,"question":18,"related":19,"source":27,"type":38},[],"2023-05-07 22:58:31",84480188,[8,9,10,11],"不存在三角分解","不存在Doolittle分解","非奇异","一阶顺序主子式为零",{"courseId":13,"courseImg":14,"courseName":15,"workId":16,"workName":17},"1000011058","https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fe897508696b95a312b0f5f065eec61e1.jpeg","高等工程数学","29064272","高等工程数学教程考试","\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fa1178d771aa85be697585c83d2929e38.png\">对于矩阵 ,( )一定成立",[20,29,39,48,58,67,76,79,84,89],{"answer":21,"createTime":5,"id":22,"options":23,"question":26,"source":27,"type":28},[],84480171,[24,25],"对","错","设\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fe09df43bf935eeea5e147c5e805e07f9.png\">对称,经Gauss顺序消去法一步后A变为\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fc1cb6c8f94169f46e6d9ed903f1dfe16.png\">其中\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F2964db61c68b5976c2d33393f2b955b2.png\">是\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fda8a0a59ce162768746b3b5c6598e99b.png\">阶矩阵,那么\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F2964db61c68b5976c2d33393f2b955b2.png\">仍为对称阵","v2",3,{"answer":30,"createTime":5,"id":31,"options":32,"question":37,"source":27,"type":38},[],84480174,[33,34,35,36],"若系数矩阵A实对称正定,且松弛因子\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F97f06191796f7fd55a89b77a33a911be.png\">,则SOR法收敛","若系数矩阵A严格对角占优,则SOR法收敛的充要条件是松弛因子\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F7e4f94936af664c9b98ab84fe745314b.png\">","J迭代法和G-S迭代法的敛散性无关联","选取的松弛因子不同,SOR迭代法的敛散性或收敛速度不同","下面说法正确的是",1,{"answer":40,"createTime":5,"id":41,"options":42,"question":47,"source":27,"type":38},[],84480176,[43,44,45,46],"共轭梯度法第k步迭代点是经过初始点由各步搜索方向p0,p1,…,pk-1张成的空间中的极小值点,因此具有某种"全局"最优性","不计舍入误差,共轭梯度法至多经n步便得线性方程组的解","最速下降法和共轭梯度法都是极小化方法","最速下降法的每一步的搜索方向为上一步迭代点的负梯度方向","下面说法正确的是( )",{"answer":49,"createTime":5,"id":50,"options":51,"question":56,"source":27,"type":57},[],84480177,[52,53,54,55],"6\u002F55(1,-6,1)T, 114\u002F552(-1,18,-1)T","114\u002F552(-1,18,-1)T, 6\u002F55(1,-6,1)T","6\u002F55(-1,6,-1)T, 114\u002F552(-1,18,-1)T","114\u002F552(-1,18,-1)T, 6\u002F55(-1,6,-1)T","用最速下降法和共轭梯度法求解方程组:\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fce2e0bb1c4a20d9fe8993ba479754c18.png\">选取(0,0,0)T作为初值,则第二步迭代的搜索方向分别为( )",0,{"answer":59,"createTime":5,"id":60,"options":61,"question":66,"source":27,"type":57},[],84480178,[62,63,64,65],"-5\u002F3","5\u002F3","7\u002F3","3","用列主元法解线性方程组:\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fa0da32f77ccc1255bc3e8b8d56571c53.png\">第二步消元的主元是( )",{"answer":68,"createTime":5,"id":69,"options":70,"question":75,"source":27,"type":57},[],84480187,[71,72,73,74],"x=AA+b","x=A+Ab","x=A+b","都不是","下列哪项是矛盾方程组Ax=b的极小范数最小二乘解( )",{"answer":77,"createTime":5,"id":6,"options":78,"question":18,"source":27,"type":38},[],[8,9,10,11],{"answer":80,"createTime":5,"id":81,"options":82,"question":83,"source":27,"type":28},[],84480191,[24,25],"求解无约束非线性优化的FR共轭梯度法的\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fff79bca7a7caca8ba0e83a2e96177975.png\">表达为\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F4fe19217fe5833562ae3288a14b4fdb4.png\">",{"answer":85,"createTime":5,"id":86,"options":87,"question":88,"source":27,"type":28},[],84480197,[24,25],"若系数矩阵A严格对角占优,则J迭代法、G-S迭代法和SOR法均收敛",{"answer":90,"createTime":5,"id":91,"options":92,"question":93,"source":27,"type":28},[],84480199,[24,25],"若A是列满秩矩阵,则矛盾方程组Ax=b的最小二乘解x0满足AHAx0=AHb,且有唯一解x0"]