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March 29, 2024, 09:10:29 am

Author Topic: Mathematics Question Thread  (Read 1296919 times)  Share 

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Vinhtran

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Re: Mathematics Question Thread
« Reply #405 on: September 28, 2016, 06:38:35 pm »
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I'm confused on how they found c in the tangent equation, please help.
Determine the equation of the tangent to the graph of y = x^(2)e^(x) + 1, x ≥ 0 at any point where x = a

MightyBeh

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Re: Mathematics Question Thread
« Reply #406 on: September 28, 2016, 06:59:20 pm »
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I'm confused on how they found c in the tangent equation, please help.
Determine the equation of the tangent to the graph of y = x^(2)e^(x) + 1, x ≥ 0 at any point where x = a
Derivative of y at x=a will give you the gradient of the tangent. Subbing x=a back into y will give you a point, that the tangent will also pass through. Subbing this point into your tangent equation will give you c.
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RuiAce

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Re: Mathematics Question Thread
« Reply #407 on: September 28, 2016, 06:59:52 pm »
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I'm confused on how they found c in the tangent equation, please help.
Determine the equation of the tangent to the graph of y = x^(2)e^(x) + 1, x ≥ 0 at any point where x = a


Vinhtran

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Re: Mathematics Question Thread
« Reply #408 on: September 28, 2016, 07:16:29 pm »
+1
Didn't think about using gradient formula, thank you both

samuels1999

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Re: Mathematics Question Thread
« Reply #409 on: September 29, 2016, 09:21:25 pm »
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Hi jamonwindeyer and jakeislove

I just wanted to know what text books you used for physics (jacaranda?) and maths (cambridge?)

Thanks
"If you can't explain it simply, you do not understand it well enough" -Albert Einstein
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RuiAce

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Re: Mathematics Question Thread
« Reply #410 on: September 29, 2016, 09:27:55 pm »
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Hi jamonwindeyer and jakeislove

I just wanted to know what text books you used for physics (jacaranda?) and maths (cambridge?)

Thanks
Your textbook for mathematics doesn't matter at the end of the day, because you're going to be glued to past papers.

Though with that out of the way, in general Cambridge is the recommended textbook. This is due to its wide range of coverage and its suitability in addressing all levels of student capability. It starts off nice and easy for people to start grasping the basics and still has a range of challenging problems for the very keen student.

In general, I do advocate for it. But I didn't use it. I used Fitzpatrick for 2U and Maths in Focus (this textbook is actually strongly advised against under normal situations) for 3U.

Note that every textbook has its pros and cons. An answer cannot be made definitively as it is entirely based off personal preference. Cambridge just happens to be the stronger option in general.


With physics, Jacaranda and Physics in Focus are the two recommended. Not the place to be discussing it though.

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jakesilove

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Re: Mathematics Question Thread
« Reply #411 on: September 29, 2016, 09:29:03 pm »
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Your textbook for mathematics doesn't matter at the end of the day, because you're going to be glued to past papers.

Though with that out of the way, in general Cambridge is the recommended textbook. This is due to its wide range of coverage and its suitability in addressing all levels of student capability. It starts off nice and easy for people to start grasping the basics and still has a range of challenging problems for the very keen student.

In general, I do advocate for it. But I didn't use it. I used Fitzpatrick for 2U and Maths in Focus (this textbook is actually strongly advised against under normal situations) for 3U.

Note that every textbook has its pros and cons. An answer cannot be made definitively as it is entirely based off personal preference. Cambridge just happens to be the stronger option in general.


With physics, Jacaranda and Physics in Focus are the two recommended. Not the place to be discussing it though.

Jake's surname is "Silove"

Agree completely with the above
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jamonwindeyer

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Re: Mathematics Question Thread
« Reply #412 on: September 29, 2016, 09:32:08 pm »
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Hi jamonwindeyer and jakeislove

I just wanted to know what text books you used for physics (jacaranda?) and maths (cambridge?)

Thanks

To answer the question, Physics in Focus, and I used a very old textbook by Jones and Couchman for 3 Unit Mathematics (called, incidentally, 3 Unit Mathematics). In my opinion, actually better than Maths in Focus/Cambridge, based on the exposure I've had to the other two :)

But yeah, really doesn't matter which you get, all have pros and cons :) :)

pels

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Re: Mathematics Question Thread
« Reply #413 on: September 30, 2016, 11:44:46 am »
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Hey all.

Quick question here

Evaluate lim θ -> 0
Of (sin2θ)/3θ

Im not sure how to arrive at the final answer.

Any help would be appreciated.

cheers :^)

RuiAce

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Mathematics Question Thread
« Reply #414 on: September 30, 2016, 11:58:54 am »
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Hey all.

Quick question here

Evaluate lim θ -> 0
Of (sin2θ)/3θ

Im not sure how to arrive at the final answer.

Any help would be appreciated.

cheers :^)

« Last Edit: September 30, 2016, 06:04:53 pm by RuiAce »

pels

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Re: Mathematics Question Thread
« Reply #415 on: September 30, 2016, 04:45:28 pm »
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Can you explain how sin2θ/2θ = 1

Since sinx/x = 0, i still don't understand the above

call.me.blueberry

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Re: Mathematics Question Thread
« Reply #416 on: September 30, 2016, 06:00:26 pm »
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Can you explain how sin2θ/2θ = 1

Since sinx/x = 0, i still don't understand the above

for the limit of sin(x)/(x), is x approaching 0?

I check with wolframalpha the limit is =1 too: https://www.wolframalpha.com/input/?i=lim+x-%3E+0+sin(x)%2F(x)
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RuiAce

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Mathematics Question Thread
« Reply #417 on: September 30, 2016, 06:03:32 pm »
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Can you explain how sin2θ/2θ = 1

Since sinx/x = 0, i still don't understand the above
My apologies, I made a mistake in typing. That 0 is meant to be a 1. I will fix that now
for the limit of sin(x)/(x), is x approaching 0?

I check with wolframalpha the limit is =1 too: https://www.wolframalpha.com/input/?i=lim+x-%3E+0+sin(x)%2F(x)
Yes. x goes to 0.
« Last Edit: September 30, 2016, 06:08:05 pm by RuiAce »

lozil

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Re: Mathematics Question Thread
« Reply #418 on: September 30, 2016, 08:01:14 pm »
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I'd appreciate if someone could help me with this one:

Thanks!

jakesilove

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Re: Mathematics Question Thread
« Reply #419 on: September 30, 2016, 09:15:11 pm »
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I'd appreciate if someone could help me with this one:

Thanks!

Hey! So, essentially, we need to find a value for k such that the area under the curve from -6 to 4 equals the area under the curve from 4 to k (that way, the negative and positive areas cancel out!

You can find the area under the first section in many ways; there's a formula, which I don't know, so I'll divide it into a triangle and a rectangle. The rectangle has area 10*2, and the triangle has area 10*(1/2)*3, so the total area will be 35 units squared.

The area of the second section can be found in the same way; the rectangle will have area (k-4)(4) and the triangle will have area (1/2)(k-4)(2). So, the total area will be (k-4)(4)+(1/2)(k-4)(2). Now, we need these two areas to be the same, so






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