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I figured that since us GOG members have actively decided to be anti-DRM we've got to be smart cookies. If any place was a good place to get an answer, it'd be the GOG community.

Question: The tangent to the function f(x)=(x)cubed-6(x) when x=1 intersects the curve at another point. What is this point?

Keep in mind I don't know derivatives yet so the answer in the advanced functions way is what I need. I used a graphing calculator to find the point, but I don't know how to show my work. Thanks in advance.
This question / problem has been solved by ZFRimage
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I honestly don't completely understand what you mean by "advanced functions way". There are a couple of methods of finding the correct answer without using derivatives, but...

While I don't mind giving homework help over forums in general, this looks like it's a textbook example problem i.e. something you should be able to solve yourself if you're studying this.

Unless you're not studying this and it's for something outside your curriculum?
Post edited January 18, 2015 by ZFR
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InaneKorruption: I figured that since us GOG members have actively decided to be anti-DRM we've got to be smart cookies. If any place was a good place to get an answer, it'd be the GOG community.

Question: The tangent to the function f(x)=(x)cubed-6(x) when x=1 intersects the curve at another point. What is this point?

Keep in mind I don't know derivatives yet so the answer in the advanced functions way is what I need. I used a graphing calculator to find the point, but I don't know how to show my work. Thanks in advance.
Do your own homework! :P
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ZFR: I honestly don't completely understand what you mean by "advanced functions way". There are a couple of methods of finding the correct answer without using derivatives, but...

While I don't mind giving homework help over forums in general, this looks like it's a textbook example problem i.e. something you should be able to solve yourself if you're studying this.

Unless you're not studying this and it's for something outside your curriculum?
It's a thinking question our teacher gave us because in about two weeks we're starting calculus, but go ahead, hit me with the calculus answer if you can. Any help would be appreciated.
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ZFR: I honestly don't completely understand what you mean by "advanced functions way". There are a couple of methods of finding the correct answer without using derivatives, but...

While I don't mind giving homework help over forums in general, this looks like it's a textbook example problem i.e. something you should be able to solve yourself if you're studying this.

Unless you're not studying this and it's for something outside your curriculum?
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InaneKorruption: It's a thinking question our teacher gave us because in about two weeks we're starting calculus, but go ahead, hit me with the calculus answer if you can. Any help would be appreciated.
OK, fair enough. With calculus it's extremely easy. But, if it's a thinking question your teacher wants you to solve without using calculus, here is a method:

METHOD 1 (without using derivatives)

Consider constructing a circle that is a tangent to that function at that point, then find the tangent to the circle at that point. Example. Try figuring out the details yourself, I'm sure your teacher will appreciate the work you put this.

Once you do this, you'll really appreciate how much easier it is to do it by learning calculus. Using derivatives:

METHOD 2 (using derivatives)

The derivative of the function is:
f'(x) = 3x^2 - 6 (you'll learn why when you start calculus)

So the derivative at the point x=1 is
f'(1) = .... (complete this yourself by substituting x=1 to the equation above)

so the tangent is a line with slope=f'(1) (the value you get above)

Find the value of the function at the point x=1
f(1) = ... (complete this yourself)

So your tangent is a line with slope=f'(1) and passing throuhg the point ( 1, f(1) )

Given the this you should be able to write an equation for the tangent line.

-----------------------------

Once you get your tangent equation using either of the methods above, finding intersection points should be trivial (just form an equation).

Hope this is clear.
Post edited January 18, 2015 by ZFR
The answer is 42.
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tinyE: The answer is 42.
Sadly, my math teacher doesn't think so.
OK, that post should get you in the right direction. I hope it's clear. Try doing both methods, compare and see if you get the same answer.

If you're stuck, ask away. I'll gladly help if you're actually putting effort into trying to get this yourself.
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InaneKorruption: Sadly, my math teacher doesn't think so.
Then he's tragically, egregiously wrong.
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ZFR: OK, that post should get you in the right direction. I hope it's clear. Try doing both methods, compare and see if you get the same answer.

If you're stuck, ask away. I'll gladly help if you're actually putting effort into trying to get this yourself.
I was wondering if using the msecant =(f(x+h)-f(x)) / (h+x-h) to find the slope of the tangent would work. I'm usong method 1 and it seems like an arbitrary step to find the slope of the tangent. Unless it shows something different.
Post edited January 19, 2015 by InaneKorruption
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InaneKorruption: I was wondering if using the msecant =(f(x+h)-f(x)) / (h+x-h) to find the slope of the tangent would work.
Yes, but there is a mistake in the denominator. It should be x+h-x which is equal to h.

EDIT: also remember, to get the slope what you want is the limit as h approaches 0. That's in fact what a derivative is.
Post edited January 19, 2015 by ZFR
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InaneKorruption: I was wondering if using the msecant =(f(x+h)-f(x)) / (h+x-h) to find the slope of the tangent would work.
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ZFR: Yes, but there is a mistake in the denominator. It should be x+h-x which is equal to h.
Oh yeah. Sorry. So it would work right?
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InaneKorruption: Oh yeah. Sorry. So it would work right?
Yes, that's a method that will work. It's just like finding the derivative.
Post edited January 19, 2015 by ZFR
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InaneKorruption: Oh yeah. Sorry. So it would work right?
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ZFR: Yes, that's a method that will work :)
Well that just made everything easier.