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# The Soc for People of 'GRDCT2008' Mk VI watch

1. (Original post by piece_by_piece)
Fainted this morning

I wanna sleeep forever.

2. worlds strictest parents
4. shameful
5. Someone good at maths solve this for me

sin4A = cos2A

NOW!
6. (Original post by ArchedEdge)
Someone good at maths solve this for me

sin4A = cos2A

NOW!
subs for cos2A with the double angle formula that has sin in ..
1-sin2A I think...
then rearrange
??
7. over my third gold.
8. (Original post by Malsy)
over my third gold.

well in!
9. I cannot actually believe 2117 + 1338 reps omg like most given ever to one person in one day?
10. (Original post by raceforthefishman)
subs for cos2A with the double angle formula that has sin in ..
1-sin2A I think...
then rearrange
??
Actually no, I figured it out mostly, but there's still a bit majorly pissing me off.

Sub sin4A for 2sin2Acos2A

Divide both sides by cos2a

So 2sin2A = 1

Divide by 2

sin2A=0.5
Inverse sin, 2A = 30 degrees
which is also 150, divide both by 2 to get 15 and 75, which are only 2 out of 4 possible answers.

Apparently 45 and 135 are valid answers as well, except I have no idea how
11. Malsy I swear that you only got your first a couple of months ago

but congrats
12. sucky having a job

Well done malsy
13. (Original post by ArchedEdge)
Actually no, I figured it out mostly, but there's still a bit majorly pissing me off.

Sub sin4A for 2sin2Acos2A

Divide both sides by cos2a

So 2sin2A = 1

Divide by 2

sin2A=0.5
Inverse sin, 2A = 30 degrees
which is also 150, divide both by 2 to get 15 and 75, which are only 2 out of 4 possible answers.

Apparently 45 and 135 are valid answers as well, except I have no idea how
Im sure you'll have to use the formulas!!!!
What topic is it in?
Now is the time when my teacher would go crazy with his 'but you'll lose values'

Where ghoshy when you need him
14. (Original post by raceforthefishman)
Im sure you'll have to use the formulas!!!!
What topic is it in?
Now is the time when my teacher would go crazy with his 'but you'll lose values'

Where ghoshy when you need him
Nah it's cool now, my dad figured it out.
Do you want me to explain or are you not bothered?
15. (Original post by ArchedEdge)
Nah it's cool now, my dad figured it out.
Do you want me to explain or are you not bothered?
Ye go for it...explain away, its all good!
16. (Original post by raceforthefishman)
Ye go for it...explain away, its all good!
Basically the way I did it is one way of doing it, but by doing it that way, you lose the equation where cos2A = 0 as well.

So you do the whole sin4A = 2sin2Acos2A

But take away cos2A from both sides

So you get,

cos2A(2sin2A-1) = 0

And then just set cos2A to 0, AND 2sin2a=1 etc
17. Why have I never done that maths question.
18. (Original post by ArchedEdge)
Basically the way I did it is one way of doing it, but by doing it that way, you lose the equation where cos2A = 0 as well.

So you do the whole sin4A = 2sin2Acos2A

But take away cos2A from both sides

So you get,

cos2A(2sin2A-1) = 0

And then just set cos2A to 0, AND 2sin2a=1 etc
Riiiiight

Thanks
Glad to have been no help whatsoever
19. (Original post by Kuriso)
Malsy I swear that you only got your first a couple of months ago

but congrats

I know; it's honestly immense. I thought the one would be enough, tbh, and that I'd never get further or be bothered, tbh

(Original post by letsdothetimewarpagain)
sucky having a job

Well done malsy

Thanks.
20. (Original post by Malsy)
I know; it's honestly immense. I thought the one would be enough, tbh, and that I'd never get further or be bothered, tbh
A quote outside chat (I really don't get a lot of these )

soon enough your rep will be more like buses and you'll get none for months

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