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1. Hey guys,

Could someone please show me how to do the following questions. I would be very grateful.
Thanks in advance to anyone who helps

For part A) do I divide 1 by 3 first then square root or square root first then divide by 3?
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2. For questions like these, your aim first is to isolate the trign(x) function so you can then take the nth root of both sides. So what you thought of doing first is correct
3. For part A) Divide 1 by 3 first then square root (I think)
4. (Original post by Aty100)
Hey guys,

Could someone please show me how to do the following questions. I would be very grateful.
Thanks in advance to anyone who helps

For part A) do I divide 1 by 3 first then square root or square root first then divide by 3?
remember that

is the same as

yay it came out right
5. It doesn't matter if you divide 1 by 3 first or do the square root first (and then divide by root 3, not 3). Bear in mind there may be two possible real solutions for a quadratic if the discriminant is >0.

Both those equations involve special angles, which you should memorise. In this case the special angles are sin(pi/4) = 1/(root2), sin(pi/6) = 1/2 and cos(pi/6) = (root3)/2.
6. (Original post by Student403)
For questions like these, your aim first is to isolate the trign(x) function so you can then take the nth root of both sides. So what you thought of doing first is correct
wait a sec, but root 1 is 1????
7. (Original post by thefatone)
remember that

is the same as

yay it came out right
Came out right but it's wrong .
8. (Original post by thefatone)
wait a sec, but root 1 is 1????
Huh?
9. (Original post by thefatone)
remember that

is the same as

yay it came out right
Nooo
10. (Original post by Unkempt_One)
Came out right but it's wrong .
remember that

is the same as???

?????
11. (Original post by thefatone)
remember that

is the same as???

?????
Yup
12. (Original post by Student403)
Nooo
was it you?

i remember doing trig myself and i remember taking out a factor instead of doing a quadratic and someone posted nooooooooooooooo with a funny picture of someone holding their head saying nooooooooooooo
13. (Original post by thefatone)
remember that

is the same as???

?????
Umm, yes. But it really doesn't matter in which order you deal with the coefficient lol. That's basic algebra. The key points here are quadratics and special angles.
14. (Original post by thefatone)
was it you?

i remember doing trig myself and i remember taking out a factor instead of doing a quadratic and someone posted nooooooooooooooo with a funny picture of someone holding their head saying nooooooooooooo
Probably not
15. (Original post by Student403)
Probably not
hmmm might have been TeeEm ...
16. (Original post by Student403)
For questions like these, your aim first is to isolate the trign(x) function so you can then take the nth root of both sides. So what you thought of doing first is correct
To extend this, in general you might not be able to 'isolate' the sin/cos function neatly. Anticipating harder questions you might get asked, you might have quadratic equations where the linear component is not zero eg. sin^2 - ((1+root3)/2)sin + (root3)/4. In general you're finding possible solutions of the quadratic, figuring out which of those solutions lie in the range of the trigonometric function and finding what values of x map to those solutions.
17. (Original post by Student403)
Probably not
found it
http://www.thestudentroom.co.uk/show...ght=trig%20mk4
18. (Original post by thefatone)
was it you?

i remember doing trig myself and i remember taking out a factor instead of doing a quadratic and someone posted nooooooooooooooo with a funny picture of someone holding their head saying nooooooooooooo
Nevermind you were talking about something different than I thought.
19. (Original post by Unkempt_One)
Nevermind you were talking about something different than I thought.
i found the thread which that happened check it out ^^^ a few posts up
20. (Original post by Unkempt_One)
To extend this, in general you might not be able to 'isolate' the sin/cos function neatly. Anticipating harder questions you might get asked, you might have quadratic equations where the linear component is not zero eg. sin^2 - ((1+root3)/2)sin + (root3)/4. In general you're finding possible solutions of the quadratic, figuring out which of those solutions lie in the range of the trigonometric function and finding what values of x map to those solutions.
Right

Nice find :P

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