2008 Second Semester MATHS课程问答帖(请用英文提问)

z-score

303B25会在奥大板块长期提供MATHS课程的免费问答。本贴为大家提供assignment, course book, test & exam questions的帮助。

303B25 will offer long term help with MATHS papers in The University of Auckland sub-forum. In this post you could ask questions regarding assignment, course book, test & exam questions.

303B25可以帮助的数学课程:

102 (4楼)
108 (5楼)
150 (6楼)
208 (7楼)
250 (8楼)
255 (9楼)

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[ 本帖最后由 z-score 于 2008-8-4 12:11 编辑 ]

小粘糕

hello?help with math108 ass1 plz

thear

;32;;32;

thear

duclover

有米人做MATHS 326 assignment 1呢？？？？？

bendy1111

09 first semester,maths 208

有人在做assignment 1吗，讨论一下啊

阿Ting

The question asks us to transform the augmented matrix below into rref
1         0             2            1
2         1             3            m
-2        m           -5           -3
The rref i got is:
1          0            2             1
0          1             -1           m - 2
0           0           m - 1         - m^2 + 2m - 1
im really not good at this rref thing, jst wondering if i did this right. Can u take a look at it for me please? Thank you very much!

nickychiu

居然是你，果然是你。

天外飞猪

天哪。半学期过去了。
还在upgrade啊？？
什么时候才可以看见往年的assign呢。。。

nickychiu

math 108
if we want to find out there is "a unique solution" for the value of m in such as this example
x      y       z
1     0      1    1
0   1+m  1   m-3
0  -m/3   1    1/3

a unique solution is to make all values of 3rd row X Y Z to be "0"
how could i make this happen?

册那

how 2 prove that Null(A^T*A)=Null(A)? cheers.

摇得你好滚

why did i got 1, -3, 4? i've checked again and again...

摇得你好滚

and if we want to normalize a vecvor u, do we write like this: u/(u*u) ?

摇得你好滚

Given the linear system
                                          (1    1    1)                     (5)
                                          (1    1    0)      (x1)         (4)
                              Ax =                             (x2)    =
                                           (0    1    1)      (x3)         (4)
                                           (1    0    1)                      (4)
How to show that this system is inconsistent?

Why do i get it is consistent after i row reduce it.......?

And what is the difference between "calculate the normal system" and "solve the normal system"?

没蚊香的黑夜

Help plz with MATHS 208

A =

1 2 0
2 1 0
0 0 4
.
Find an orthogonal diagonalisation of A. That is ...
(a) Find the eigenvalues.
(b) For each eigenvalue, find an eigenvector.
(c) Normalize each eigenvector. (Make it have unit length.)
(d) Check that in this case the 3 eigenvectors are orthogonal.
(e) Diagonalize A, so that
A = CDCT ,
where C is an orthogonal matrix. (For orthogonal matrices C−1 = CT .)

I  can only find one eigenvalue which is 4.......but in (d), it seems like there should be 3 eigenvalues.....anybody help with this question?

江儿

math162 Q3 b

册那

maths250 assignment1 question 9.
Let n>=3. which of the following sets of vectors u = (x1,...,xn) in R^n are subspaces of R^n?
(a)all u such that x1>=0
give reasons to your answer.

cheers.

akl

Maths 108 Assignment 1

Question 6 (b) (c) (d)

How do u type in the commands in the Matlab? Thanks!

bendy1111

maths 108

question 8

consider the function defined by h(x)=1/(sqr(x^2 -k), where k is a constant.

a) find a value of k for which  h has no vertical asymptotes.
b) how does the natural domain of h depend on the value of k?
c) what valuees of k give h two vertical asymptote?

help me plz

摇得你好滚

Queation:  Find the characteristic equation for the matrix A:
                                        1  2  1
                                  A = 1  0  1
                                         1  6  1

THX.

clement001

A piecewise function f is defined by:
f(x) = x + k when x is less than 1, and
f(x) = 3 otherwise.
What value of k makes f continuous at x = 1?

a.  3
b.  1
c   2
d   no value of k




HOW TO CALCULATE
i have no idea

摇得你好滚

thanks, our lector just start topic 5 this morning so got it now