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Maths
Former Member
Posts: 1,876,323 The Mix Honorary Guru
Right im doing A2 maths, P3 and im stuck and need help badly!! its about double angle formulae. Can any one help???? i cant do it! :eek2:
Carrie x
Carrie x
Post edited by JustV on
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I'm not really certain what your exact problem is? Which aspect are you stuck with?
That's the stuff with the Sin A + B = whatever, right?
Don't worry, I think everyone finds Maths challenging!
sin2x + sinx = 0
solve for -180 < 0 < 180
i have a few like that and i have NO IDEA!!!!
thus you have
2sinxcosx + sinx = 0
factorising,
sinx(2+cosx) = 0
2+cosx will never be 0 as cosx can only take values from 1 to -1, and even at -1 2+cosx will be 1. Thus sinx must be 0 for the solution to the equation.
sinx = 0
thus x = 0 is the solution.
Just wanted to compare it to the Danish levels.
Thanks.
Edited to say: Does that make sense?!
O well, no more until summer. Alkyhol here I come!!!!!!!!!
Are you sure that's how it factorises, not:
2sinxcosx + sinx = 0
sinx (2cosx + 1) = 0
No?
If your explanation meant that she was doing maths on a higher level, then yes, it made sense.
If she doesn't, then it... didn't
Tell me about it! I did AQA Specification A and it was horrible. But it could've been worse, though I had no idea how to work out the probability of a Type II Error - our teacher told us we didn't need to know! :mad:
DJP I believe your factorising is correct.
DJP's factorisation was correct.
What the bloody hell is a type II error? Standard deviation, mean, chisquared, what happened to these in your course Alan? Prehaps the types are random and systematical errors?
Are any of you lot doing complex numbers and/ or vector algebra? If you're not you should read about them, thay are real handy.
:cool:
What are the diffent types of maths a2 or as that you can take?
is it something like applied and pure or something?
I have to take maths for 6 form for the course I want to get into and i really hate it.
:mad:
but from inspecition, but for sin(2x)+sin(x)=0
x has to be 0 degrees because all parts will equal 0!