VCE Methods Question Thread!

[M_BONG]

be careful with nsolve, i'm not saying you should avoid using it but depending on the complexity of the equation you ask it to compute it can take a lot longer than solving a regular, symbolic equation
for example asking it to solve normal distribution things for varying parameters can take quite a while, or i remember it taking quite a while when I tried to do the last question off some insight exam 2 last year using it.

awesome method for things like this question though!

and yes, it's just nsolve(equation(s), variable) instead of solve(equation(s), variable)

Really? nsolve is always the fastest for me. Wiith normal solve, my CAS always crashes in equations with large powers but nsolve does it in a split second.

But you have to specify a domain with nsolve , otherwise it will spit out the lowest answer and that is the reason why it's so fast (whereas solve function goes through all solutions). Also, with nsolve, you can (afaik) only solve for one variable.

[knightrider]

For calculus and antidifferentiation
What formulas are you required to know in terms of shapes for these topics

and also why is antidifferentiation the same as integration

[jessss0407]

Hey guys!
I was wondering, under what conditions would y=x^3 have no stationary points?

Thanks!

[keltingmeith]

Hey guys!
I was wondering, under what conditions would y=x^3 have no stationary points?

Thanks!

Let's consider the family of cubics , then its derivative is . Equating this to zero, then the cubic will have a stationery point at . Now, for there to be no solutions (i.e. the cubic has no stationery points), then the discriminant will be less than zero. So, . So, there will be no stationery points if the inequality holds.

[M-D]

Hi guys,

Could someone please explain in simple terms the last part of VCAA 2007 Exam 2 Section 2. I mean part fii. It's a bit confusing the way you must change from knowing the value of p to then find b.

Thanks in advance. 

[knightrider]

For calculus and antidifferentiation
What formulas are you required to know in terms of shapes for these topics

and also why is antidifferentiation the same as integration

What does it mean when it says  X′P′ = 10 and X′C′ = 30 this is from 2013 exam 2

[keltingmeith]

For calculus and antidifferentiation
What formulas are you required to know in terms of shapes for these topics

and also why is antidifferentiation the same as integration

For the first question, you're required to know every formula on your formula sheet - AFAIK, no others are expected knowledge, but check the study design to be sure.

And I'm not quite sure what you mean by the second question... However, it's possibly that the Fundamental Theorem of Calculus has the answer you want?

[myanacondadont]

Hey I need some help with an inverse function. Some reason I can't get it, do I need to complete the square?

Define f^-1 where f(x)=      x^2 + 2x/3 + 3    (-∞, -1/3]

[keltingmeith]

Hey I need some help with an inverse function. Some reason I can't get it, do I need to complete the square?

Define f^-1 where f(x)=      x^2 + 2x/3 + 3    (-∞, -1/3]

Yes - you should be completing the square for any quadratic you need to find the inverse of.

[knightrider]

What does it mean when it says  X′P′ = 10 and X′C′ = 30 this is from 2013 exam 2

[myanacondadont]

Yes - you should be completing the square for any quadratic you need to find the inverse of.

Seriously? I haven't even heard completing the square mentioned since year 11. My teacher has not said it once all year, it's as if it doesn't even exist. Damn; gotta relearn :<

[keltingmeith]

Seriously? I haven't even heard completing the square mentioned since year 11. My teacher has not said it once all year, it's as if it doesn't even exist. Damn; gotta relearn :<

Completing the square is an essential skill - however, you can often gloss over it by using the quadratic equation, which is why a lot of teachers don't comment on it.

This is one case where completing the square is easier than factor ising directly or using the quadratic equation. (first won't help you at all, second is a lot more trouble than it's worth...)

On that, anything you learned in year 11 you should know for your exams. It is all assessible, units 1/2 are assumed knowledge.

[myanacondadont]

Completing the square is an essential skill - however, you can often gloss over it by using the quadratic equation, which is why a lot of teachers don't comment on it.

This is one case where completing the square is easier than factor ising directly or using the quadratic equation. (first won't help you at all, second is a lot more trouble than it's worth...)

On that, anything you learned in year 11 you should know for your exams. It is all assessible, units 1/2 are assumed knowledge.

True, true. Thanks

edit: thankyou very much it worked.

[knightrider]

How would you find the antiderivative of the following



and also how do you antidifferentiate
and

[psyxwar]

How would you find the antiderivative of the following



and also how do you antidifferentiate
and

Have a read through the chapter of integration in your textbook. For the first one you'd want to divide it through first though.