VCE Methods Question Thread!

[Robert123]

If X and P are coordinates, what does the equation XY=10 mean? This question is paraphrase from vcaa 2013 exam 2, question 1fi so if you can help with that too, that would be great 

[faredcarsking123]

If X and P are coordinates, what does the equation XY=10 mean? This question is paraphrase from vcaa 2013 exam 2, question 1fi so if you can help with that too, that would be great 

I believe it means distance XY

For the first part it is the Y distance

For the second part (from memory X'C'=30) is the x distance from C' to X'

[soNasty]

Given that find and
and

I found that and
using triangles
is that it?
I dont have the answers

[GeniDoi]

Given that find and
and

I found that and
using triangles
is that it?
I dont have the answers

Yeah those are correct. You need to draw a triangle for full marks though.

[soNasty]

Yeah those are correct. You need to draw a triangle for full marks though.

yeah i used a triangle!
Alright sweet, thanks

[soNasty]

Question! In what instance would I equate
m=dy/dx to solve for an unknown?

[keltingmeith]

Question! In what instance would I equate
m=dy/dx to solve for an unknown?

When you want to now the derivative at a point and know the equation of the tangent to the curve at that point.

[Reus]

yeah i used a triangle!
Alright sweet, thanks

Can you show us your working? Pls

[soNasty]

Can you show us your working? Pls

so i knew that cos(x)=\frac{\sqrt{3}}{5} and i drew that triangle using the whole sohcahtoa stuff

[Zealous]

Given that find and
and

I found that and
using triangles
is that it?
I dont have the answers

I think you've overlooked the quadrant  - 'x' is in the second quadrant so both cosine and tangent are negative.

You could also just do an algebraic method:

[Reus]

(Image removed from quote.)

so i knew that cos(x)=\frac{\sqrt{3}}{5} and i drew that triangle using the whole sohcahtoa stuff

Ah I see so you had to work out the adjacent through Pythagorus. Interesting stuff Thanks! Is this on any particular exam?

[Reus]

I thought for the normal equation we had to make it equal to zero? And tangent was y= blah blah

[Kaleidoscope]

Hey guys, how would you solve for m?

[soNasty]

Ah I see so you had to work out the adjacent through Pythagorus. Interesting stuff Thanks! Is this on any particular exam?

nah i saw it on some guys post on VCE Discussionspace on FB!

[soNasty]

I think you've overlooked the quadrant  - 'x' is in the second quadrant so both cosine and tangent are negative.

You could also just do an algebraic method:

oh yes! i knew i was missing something! Thanks Zealous!