作者mqazz1 (无法显示)
看板Math
标题[线代] projection matrix
时间Sat Jun 11 20:03:37 2011
if P_3*3 is a projection matrix that projects any vector in R^3 onto the
vector u=[1 1 1]^T, then there must be two eigenvectors that correspond to
the eigenvalue of 0
书上写ture
请问为什麽呢?
谢谢
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1F：→ Yuchin1992 :我的想法有点笨，把P求出来再检查 06/11 20:26
2F：→ Yuchin1992 :P = A(A^T A)^(-1) A^T 06/11 20:26
3F：推 aegius1r :R3中至少有两个不平行的向量跟(1 1 1)^T垂直 06/11 22:11
4F：→ yhliu :rank(P) = 1, 故 nullity(P)=2. 06/12 02:06
5F：→ yhliu :P 不一定是垂直投影矩阵. 06/12 02:07