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# The 2010, Honorary Member Welcoming, Undergraduate Degree Results Chat Thread Mk. V watch

1. (Original post by + polarity -)
What is it?
Given that f(x) = Rcos(θ + α), and f(x) = 12cosx-4sinx
a) Find the value of R and α
(I got Rcosα = 12 and Rsinα=-4)
b) I can do, its solving a trig equation where f(x)=7

c) Write the minimum value of 12cosx-4sinx and find the smallest +ve value for which this minimum value occurs.

That coding is meant to be alpha, which has worked everywhere else

(Original post by aliluvschoc)
.
I have no idea, sorry. Make a thread in maths forum and you should get an answer
2. (Original post by Loz17)
Given that f(x) = Rcos(θ + α), and f(x) = 12cosx-4sinx
a) Find the value of R and α
(I got Rcosα = 12 and Rsinα=-4)
b) I can do, its solving a trig equation where f(x)=7

c) Write the minimum value of 12cosx-4sinx and find the smallest +ve value for which this minimum value occurs.

I have no idea, sorry. Make a thread in maths forum and you should get an answer
Is the weird bit meant to be alpha?

I can remember the lesson for this.
3. (Original post by + polarity -)

What the **** is that?
ew that is gross
4. (Original post by + polarity -)
Is the weird bit meant to be alpha?

I can remember the lesson for this.
Yea it is, I edited that in the post before you quoted
5. (Original post by Loz17)
Yea it is, I edited that in the post before you quoted
And x is theta?

(Original post by Mist786)
ew that is gross
I know!
6. (Original post by + polarity -)
And x is theta?

The x seems to have no input to it at all. All I've done so far is use double angle to expand Rcos(theta + alpha) to Rcos(theta)cos(alpha) + Rsin(theta)sin(alpha), and then got those values from that. Then you do something with pythagoras to find the value of R, but I'm stuck on that part.
7. (Original post by Loz17)

The x seems to have no input to it at all. All I've done so far is use double angle to expand Rcos(theta + alpha) to Rcos(theta)cos(alpha) + Rsin(theta)sin(alpha), and then got those values from that. Then you do something with pythagoras to find the value of R, but I'm stuck on that part.
Usually with these questions, theta is the equivalent of x, like it's a function of theta, and alpha is a little extra bit.
8. (Original post by + polarity -)
.
I think I've done a) now, it came to me in the end, but I dunno about c)

I need to go out for half an hour now anyway
9. (Original post by Loz17)
I think I've done a) now, it came to me in the end, but I dunno about c)

I need to go out for half an hour now anyway
But I just did part a.
Spoiler:
Show
10. (Original post by Loz17)
I think I've done a) now, it came to me in the end, but I dunno about c)

I need to go out for half an hour now anyway
And for part c, I'm guessing the minimum value would be where cos(x) is smallest, because it has the biggest coefficient, but I'm not sure.
11. (Original post by + polarity -)
I know!
Shocking
12. (Original post by Mist786)
Shocking
I'm actually begging it's Photoshopped, but I have a feeling that it isn't.

Can we change the subject please?
13. (Original post by + polarity -)
I'm actually begging it's Photoshopped, but I have a feeling that it isn't.

Can we change the subject please?
lol yes change the subject

I think its some american thing .. the picture
14. How do I stop my calculator showing me powers? And what would 4x10^-5 be
15. Pretty sure I've posted this before. But I'm posting it again because it's better than most rap these days.

16. (Original post by aliluvschoc)
How do I stop my calculator showing me powers? And what would 4x10^-5 be
Press the S↔D button?

It would be... 0.00004.

(Original post by Mist786)
lol yes change the subject

I think its some american thing .. the picture
I was like, um.
17. (Original post by A_master)
Furb.

You're lucky I didn't play you today. Woulda been ownage. Though the United goal against the Gers at the end was sweet
ass master being full of himself....thats a first

i DARE you to play me, RIGHT NOW

18. (Original post by + polarity -)
I was like, um.
Its bleugh

What were you searching when you found it?

I think I might do some equations in my spare time.
19. (Original post by + polarity -)
Press the S↔D button?

It would be... 0.00004.
I don't have that button.

But I have my answer now.
20. (Original post by Yas89)
ass master being full of himself....thats a first

i DARE you to play me, RIGHT NOW

Well seeing as I'm at home and I cannae be arsed coming all the way up nahhh.

I'll beat you soon though.

Still need to start this DPH essay

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