# User talk:BRIANCHAN

## Contents

MATH152/April 2015/Question B 3 (c)105:59, 17 March 2018
Spacing in integrals before dx120:25, 12 March 2018
Science:Math Exam Resources/Courses/MATH152/April 2015/Question B 4 (a)/Solution 1120:24, 12 March 2018
Minor Grammatical point001:08, 11 March 2018
MATH152/April 2015/Question B 5 (a)204:25, 3 March 2018
MATH152/April 2015/Question B 4 (b)007:43, 25 February 2018
MATH152/April 2015/Question B 3 (b)006:46, 25 February 2018
Solution120:03, 13 February 2018
Change the flags120:21, 8 February 2018

## MATH152/April 2015/Question B 3 (c)

Hi Brian,

I think it would be great if you write more precisely. For example, in MATH152/April 2015/Question B 3 (c), instead of saying that

${\displaystyle P_{1}=....}$, ${\displaystyle P_{2}=.....}$, so ${\displaystyle P_{1}=P_{2}}$, (because here P_1 is notation for plane, so the expression P_1 = ... doesn't make sense. So is ${\displaystyle P_{1}=P_{2}}$.)

we can introduce a point ${\displaystyle {\mathbf {x}}}$ on the line ${\displaystyle l_{2}}$. (See the details in the solution. I corrected it :) )

Also, can you write more details for the Gaussian elimination part in the solution of MATH152/April 2015/Question B 3 (c)?

Thanks a lot in advance.

07:10, 25 February 2018

Moreover, the solution is incorrect. The line Brian gives does not lie in ${\displaystyle P_{2}}$.

05:59, 17 March 2018

## Spacing in integrals before dx

Hi Brian,

It is customary to use \, instead of \text{ } to achieve the appropriate spacing before dx in an integral. It's good to know the spacing commands \, \; and \quad.

19:00, 5 March 2018

Thanks! This is very useful for me.

20:25, 12 March 2018

## Science:Math Exam Resources/Courses/MATH152/April 2015/Question B 4 (a)/Solution 1

Hi Brian,

I think there is a typo in this solution, the second term in the second vector is 1+i instead of i+i, and same thing happens in 4(b), but it seems that you calculated later with correct numbers. Please check and correct.

Best

Han

17:40, 7 March 2018

Thanks!

20:24, 12 March 2018

## Minor Grammatical point

Hi Brian,

Good work on your solutions! They are for the most part very well-written and easy to understand.

However, please be aware that the correct English phrases are "y equals x" and "y is equal to x." Please make sure not to write "y equals to x."

01:08, 11 March 2018

## MATH152/April 2015/Question B 5 (a)

Hi Brian,

It would be perfect if you add the way to get

${\displaystyle {\begin{pmatrix}1\\0\end{pmatrix}}=2{\begin{pmatrix}0.5\\0.5\end{pmatrix}}-{\begin{pmatrix}0\\1\end{pmatrix}}}$

Also, please don't forget to switch the flags to RS after you edit it.

Best, Hyunju

07:49, 25 February 2018

Hi Hyunju,

Thanks for letting me know about all of your suggestions. I will incorporate them into my 6 hr allotment for this week.

Brian

05:16, 1 March 2018

Thanks!

-Hyunju

04:25, 3 March 2018

## MATH152/April 2015/Question B 4 (b)

Hi Brian,

For MATH152/April 2015/Question B 4 (b), again it would be very helpful for students if you write the details about the way to get c_1 and c_2.

Also, I think the second equality is not right when you find the real form of the solution.

If I misunderstood, feel free to let me know!

Additionally, please revise your solutions first. Then, if you don't have enough time to write hints and solutions of 7 questions in MATH 110, we don't need to finish all your workload. Just work 6 hours and let me know.

Best, Hyunju

07:43, 25 February 2018

## MATH152/April 2015/Question B 3 (b)

Hi Brian,

I think the solution doesn't explain how you get the parametric form, especially the relation between x, b_1 \times b_2, and a with the plane P_2, Also, the reason why you find b_1 \times b_2.

So it would be great if you rewrite the solution. Also, please use ${\displaystyle {\mathbf {x}}}$ for vector x.

Thanks, Hyunju

06:46, 25 February 2018

## Solution

Hi Brian,

When you discussed the boundary points of convergence interval, whenever x=-2,or x=2, we end up with with the same term (it seems not affect the result). What do you think

Best, Han

19:21, 13 February 2018

Hi Han,

Brian

20:03, 13 February 2018

## Change the flags

Hi Brian,

Thanks for your work on MATH 103! Can you change the flags, once you finish writing hints and solutions?

Best, Hyunju

07:03, 8 February 2018

Hi Hyunju,

Thanks for asking me the change the flags. I just completed doing this.

Brian

20:21, 8 February 2018