数学代写-Q1
时间:2022-06-20
2022/6/20 18:01 University of New South Wales - 成绩单https://unsw.mobius.cloud/gradebook/Details.do?userId=16183&trId=3082776 1/6第 1 页,共 1 页 1 - 7 行,共 7 行 - 0试题Q1 2/2.0 查看 原始作答 未过滤的答案Let , , be vectors in .Suppose that , , , .For each of the following, select True if the statement is correct and select False if otherwise.(a) The dimension of span is 2.您的应答 正确应答True自动评分的 评分: 5/5.0(b) The dimension of span is 3.您的应答 正确应答False自动评分的 评分: 5/5.0(c) The set is a basis for .您的应答 正确应答False自动评分的 评分: 2/2.0(d) The set is a basis for span .您的应答 正确应答False自动评分的 评分: 4/4.0(e) The set is a basis for span .您的应答 正确应答True自动评分的 评分: 2/2.0查看面板- 格式 数值学生详细信息- Quiz 1 -- Week 3分数: 历时: 40 min7/10.0 已开始: 2022/6/20 AEST 上午12:24:19已结束: 2022/6/20 AEST 上午1:04:41Enhua Zhang- 考试任务邮件地址: enhua.zhang@student.unsw.edu.au已结束: 0活动的: 0学号: z5325328 等待人工阅卷: 0及格的: 0=v1⎛⎝⎜⎜⎜5−1−4−5⎞⎠⎟⎟⎟=v2⎛⎝⎜⎜⎜−3−3−45⎞⎠⎟⎟⎟=v3⎛⎝⎜⎜⎜−2480⎞⎠⎟⎟⎟R4=e1⎛⎝⎜⎜⎜1000⎞⎠⎟⎟⎟=e2⎛⎝⎜⎜⎜0100⎞⎠⎟⎟⎟=e3⎛⎝⎜⎜⎜0010⎞⎠⎟⎟⎟=e4⎛⎝⎜⎜⎜0001⎞⎠⎟⎟⎟( , )v1v2( , , )v1v2v3{ , , }v1v2v3R4{ , , }v1v2v3( , , )v1v2v3{ , }v1v2( , , )v1v2v32022/6/20 18:01 University of New South Wales - 成绩单https://unsw.mobius.cloud/gradebook/Details.do?userId=16183&trId=3082776 2/6试题(f) The set is a basis for .您的应答 正确应答False自动评分的 评分: 2/2.0总分: 1.0×5/20 + 1.0×5/20 + 1.0×2/20 + 1.0×4/20 + 1.0×2/20 + 1.0×2/20 = 25% + 25% + 10% + 20% + 10% +10%反馈信息:(a) is true. The two non-zero vectors are not scalar multiple of one another. The setis linearly independent and it spans span .(b) is false. The vector is a linear combination of . Hence the dimension ofspan is the same as the dimension of span .(c) is false. The dimension of is 4. The set of three vectors cannot be a basis.(d) is false. The set is linearly dependent because is a linearcombination of . The set cannot be a basis for the span.(e) is true. span = span , and part (a).(f) is false. The dimension of is 4. The set of five vectors cannot be a basis.Q2 1/1.0 查看 原始作答 未过滤的答案Let be invertible matrices of the same size. Suppose thatis symmetric, i.e. ;is skew-symmetric, i.e. ; andis orthogonal, i.e. .您的应答 正确应答自动评分的 评分: 1/1.0总分: 1.0×1/1 = 100%反馈信息:Note, in general, .The following properties are useful., and .{ , , , , }v1v2e2e3e4R4{ , }v1v2( , )v1v2v3{ , }v1v2( , , )v1v2v3( , )v1v2R4{ , , }v1v2v3v3{ , }v1v2( , )v1v2( , , )v1v2v3R4D, E, FD = DDTE = −EETF =FTF−1(D (ED F =E−1FT)−1)T−F FE2AB ≠ BA(AB =)−1B−1A−1(AB =)TBTAT2022/6/20 18:01 University of New South Wales - 成绩单https://unsw.mobius.cloud/gradebook/Details.do?userId=16183&trId=3082776 3/6试题Q3 1/1.0 查看 原始作答 未过滤的答案Given that is a matrix and are vectors in such thatwhere the matrix is invertible. Find the matrix such that.Enter the matrix in the box below.您的应答 正确应答自动评分的 评分: 1/1.0Note: Do not enter M = in the answer box.总分: 1.0×1/1 = 100%Q4 1/1.0 查看 原始作答 未过滤的答案Select all equations with infinitely many solutions.选项 选中的, where ,No [答案保留], where ,No [答案保留], where ,No [答案保留], where ,Yes [答案保留], where ,Yes [答案保留], where ,No [答案保留], where ,Yes [答案保留], where ,No [答案保留]反馈信息:For each of the equations, the augmented matrix is already in rowechelon form.The equation has infinitely many solutions when the right handcolumn of the row-echelon form is non-leading and there is at least one columnon the left is non-leading.A, ,v1v2v3R3⎧⎩⎨⎪⎪A = 2v1v1A = −7 + 5v2v1v2A = 6 − 7 − 5v3v1v2v3P = ( | | )v1v2v3MAP = PMM⎡⎣⎢200−7506−7−5⎤⎦⎥Ax = b A =⎛⎝⎜400500500⎞⎠⎟b =⎛⎝⎜2−10⎞⎠⎟Ax = b A =⎛⎝⎜50054031−1⎞⎠⎟b =⎛⎝⎜225⎞⎠⎟Ax = b A =⎛⎝⎜400150−103⎞⎠⎟b =⎛⎝⎜250⎞⎠⎟Ax = b A =( )4050b =( )−10Ax = b A =⎛⎝⎜40025025022550−1⎞⎠⎟b =⎛⎝⎜252⎞⎠⎟Ax = b A =⎛⎝⎜⎜⎜40001500−1030⎞⎠⎟⎟⎟b =⎛⎝⎜⎜⎜2520⎞⎠⎟⎟⎟Ax = b A =⎛⎝⎜5001−10520424⎞⎠⎟b =⎛⎝⎜−105⎞⎠⎟Ax = b A =⎛⎝⎜3005−10520⎞⎠⎟b =⎛⎝⎜224⎞⎠⎟(A|b)Ax = b2022/6/20 18:01 University of New South Wales - 成绩单https://unsw.mobius.cloud/gradebook/Details.do?userId=16183&trId=3082776 4/6试题Q5 1/2.0 查看 原始作答 未过滤的答案(a) Let be the vector space of all the polynomials of degree 7 or less.The dimension of is您的应答 正确应答8 8自动评分的 评分: 5/5.0.(b) Let and be a set of 4 vectors in .Suppose that is the subspace of spanned by .Let be the matrix with the vectors in as columns,and .The system is inconsistent. There is no solution.The system has infinitely many solutions.Fill in the following answer fields using drop down menus.The vector您的应答 正确应答is not is not自动评分的 评分: 5/5.0in the span of .The set is a linearly您的应答 正确应答independent dependent自动评分的 评分: 0/5.0set in .The dimension of您的应答 正确应答is 4 is less than 4自动评分的 评分: 0/5.0.总分: 1.0×5/20 + 1.0×5/20 + 0.0×5/20 + 0.0×5/20 = 25% + 25% + 0% + 0%反馈信息:The dimension of is .The dimension of is .For a vector space , if is a finite spanning set for and is a linearlyindependent set in , then| | dim( ) | |,where | | and | | are the number of elements of and , respectively.A basis for a vector space is a linearly independent spanning set for .The dimension of a vector space , with a finite spanning set, is the number ofvectors in a basis for .P7P7V =R6S = { ,…, }v1v4VW = span(S) V SA = ( |⋯| )v1v4Sb ∈ R6Ax = bAx = 0bWSVWMm,nm× nPnn+ 1V S V TVT ≤ V ≤ ST S T SV VVV2022/6/20 18:01 University of New South Wales - 成绩单https://unsw.mobius.cloud/gradebook/Details.do?userId=16183&trId=3082776 5/6试题Q6 0/2.0 查看 原始作答 未过滤的答案Select ALL functions which are linear transformations.您的应答 正确应答选项 3:Suppose that is a matrix andsuch that, for all .选项 4:The function defined by, for allmatrix. .Here is the set of all real matricesand is the identity matrix.反馈信息:选项 3: The function satisfies both the addition andscalar multiplication conditions.选项 4: The function does not map zero of the domainto zero of the codomain.The function definedby, for all.Suppose that is a matrixand such that, for all .The function definedby,for all .自动评分的 评分: 0/1.0总分: 0.0×1/1 = 0%A 3 × 2T : →R2R3T (v) = Av v ∈ R2F : →M22M22F (A) = 3A+ 4I 2 × 2AM222 × 2I 2 × 2T : →R3R2T⎛⎝⎜⎜x1x2x3⎞⎠⎟⎟=( )−4 − 3 −x1x2x3−3 +x2x3⎛⎝⎜⎜x1x2x3⎞⎠⎟⎟∈ R3A 3 × 2T : →R2R3T (v) = Av v ∈ R2T : →R3P2T⎛⎝⎜⎜x1x2x3⎞⎠⎟⎟=+ (2 + ) t+ ( + 3 ) x1x1x3x2x3t2⎛⎝⎜⎜x1x2x3⎞⎠⎟⎟∈ R32022/6/20 18:01 University of New South Wales - 成绩单https://unsw.mobius.cloud/gradebook/Details.do?userId=16183&trId=3082776 6/6试题Q7 1/1.0 查看 原始作答 未过滤的答案Suppose that is a basis for , where, , and .Find the vector such that its coordinate vector is given by.Enter the vector in the box below, in Maple syntax.您的应答 正确应答<10,-7,16>自动评分的 评分: 1/1.0Note: The vector , in Maple syntax, should be entered as
总分: 1.0×1/1 = 100%
反馈信息:
If the coordinate vector of with respect to the basis is
, by definition,
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