Mathematics - 2017-12-04 (page 8 of 8)

« first day (2679 days earlier) ← previous day next day → last day (2638 days later) »

randomgirl

23:00

This is my first time teaching 8th grade and I'm learning.

I mean I'm learning to teach

I'm confident about my math :)

Daminark

This is tricky, would it throw people off if you tried to put a hold on this stuff, return to just standard-fare rearranging, and then go back and try to pick this up again?

skullpatrol

Yeah, @randomgirl jumping around in the textbook is not a good idea at that age :-)

Daminark

/would it make you lose too much time?

Ah, yeah teaching for the first time is a big challenge

Hell, the first time I tried to give a one-off lecture to peers, it was a total disaster

randomgirl

I think I'm going to insert my own lesson between the book's lessons that seem to make too big of jump.

MATH ASKER

the position at time t =>0, of a particle moving at along a coordinate line is x = 10cos(t+pi/4)

skullpatrol

23:02

Try going back and covering the prerequisites.

MATH ASKER

What is the particles starting point? could anyone help me with this problem

randomgirl

I taught college algebra for a few years so I'm kinda used to a little higher thinking. I will adjust. I know I will.

Thank you guys.

skullpatrol

8th grade needs patience.

orbit-stabilizer

@MATHASKER what does t equal at the starting point

Daminark

Have the other 8th grade teachers had similar issues?

And yeah good luck @randomgirl!

randomgirl

23:04

well i'm the only math teacher at my senior/jr high school

small school

very small

skullpatrol

Wow!

MATH ASKER

0 @orbit-stabilizer

so I just plug in zero for t

orbit-stabilizer

@MATHASKER good, so do you know the answer now?

Yes.

MATH ASKER

yea i think so thanks

orbit-stabilizer

skullpatrol

23:05

Try returning to first principles @randomgirl

orbit-stabilizer

@Daminark so a semidirect product is basically where we have two groups, whose interesection is trivial and one is trivial

one is normal*?

randomgirl

You are probably right. I would rather them get this now then me reteach it to them in 9th grade or some other grade.

orbit-stabilizer

but what if we don't know what the two groups are embedded in

Daminark

That's the internal semidirect product

orbit-stabilizer

@randomgirl teach them Gaussian elimination /s

Okay, then for the external, we don't require either of them to be normal?

Daminark

23:07

The external one is of two abstract groups

skullpatrol

Building a strong foundation always works with algebra @randomgirl

MATH ASKER

If im asked to find the average rate of change of a given function given the x and y coordinates, how would I solve it? I have the function $(4x+1)^(1/2)$ over the point $[0,3/4]$ should I take the derivaitive of the function and plug in the x value, what about the y value when do i plug that in?

orbit-stabilizer

Over the point or over the interval?

MATH ASKER

over the given interval

@orbit-stabilizer

orbit-stabilizer

You have $f(x) = \frac{4x+1}{2}$ right?

MATH ASKER

23:14

no they give me f(x) = √(4x+1)

orbit-stabilizer

Okay, so you want the average rate of change. So you know you that you should take the derivative

Since you want the average, there are many ways to do it, but a common way that is taught is to plug in the end points

MATH ASKER

plug in the end point?

I know I should take the derivative but end points?

orbit-stabilizer

Have you covered integration?

MATH ASKER

yea

little bit

orbit-stabilizer

The average value of a function is defined in terms of integrals - so we should use that instead

Rather than my end points thing

tutorial.math.lamar.edu/Classes/CalcI/AvgFcnValue.aspx

MATH ASKER

23:20

the question is asking for like the rate of change issn't that the slope?

orbit-stabilizer

Slope = derivative evaluated at a point, yes

MATH ASKER

so should'nt there be a way to do it with derivatives but not integrals>

orbit-stabilizer

Are you okay with the fact that the derivative of a function gives another function that gives you the slope of the original function at each point?

Well, you don't need to take an integral if you realize what $f$ is.

MATH ASKER

yea I think thats how I was taught but i forgot how to do it lol

should i use the h method for this one

or is it the c one

orbit-stabilizer

@GFauxPas halp

Daminark

23:23

Is it true that the limit of L^p norms as p->q is the L^q norm? Assuming f is in all the applicable L^p

randomgirl

average rate of change for the function $f(x)=(4x+1)^{\frac{1}{2}}$ over the given interval would just be $\frac{f(\frac{3}{4})-f(0))}{\frac{3}{4}-0}$

oops (f(3/4)-f(0))/(3/4-0)

MATH ASKER

Oh ok thanks so no need to take derivative>

randomgirl

unless it asked for rate of change aka instantaneous rate of change at a particular value

but yeah no need for derivative

orbit-stabilizer

no need for derivative because of FTC

MATH ASKER

oh ok thanks for helping!