Trig question
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Re: Trig questionThe double angle shouldn't affect the identity,(Original post by muh123)
Is Cosec^2(2x) - Cot^2(2x) = 1
Does the double angle thing affect the identity ??
is same as, 
, where 
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Re: Trig questionYes.(Original post by muh123)
Would it still be the same if it was 2 theta aswell ?
Now insert
You could have written it as,
Still the answer would be same. -
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Re: Trig questionI was most impressed by your response to other questions but when you substituted a number to "prove" this, I was a little surprised.(Original post by raheem94)
Yes.
Now insert
You could have written it as,
Still the answer would be same.
It's never possible to prove by numbers. Instead, use algebra! -
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Re: Trig questionThe OP was stuck at a simple concept, so it was easier to prove him by numbers rather than prove.(Original post by reallytired)
I was most impressed by your response to other questions but when you substituted a number to "prove" this, I was a little surprised.
It's never possible to prove by numbers. Instead, use algebra!Last edited by raheem94; 06-04-2012 at 12:23. -
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Re: Trig questionrather than prove(Original post by raheem94)
The OP was stuck at a simple concept, so it was easier to DEMONSTRATE TO him by numbers rather than algebra.
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Re: Trig questionI don't understand why reallytired disagreed with my posts, any reason?(Original post by TenOfThem)
No problem ... after all ... your Post 2 showed the statement to be true for any substitution
Was it wrong to try to explain by using numbers, i thought it will be easier for the OP to understand in this way. -
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Re: Trig questionBy using numbers you only showed that the rule would work for theta=15 rather than a general proof
Given the level of understanding of the OP this would, imo, have been enough to show him that it would work
Reallytired seems to think a proof was required rather than a demonstration ... I guess that he was making the point that in a question that asks you to show or prove using a value to demonstrate would not be enoughLast edited by TenOfThem; 06-04-2012 at 12:54. -
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Re: Trig question(Original post by reallytired)
I was most impressed by your response to other questions but when you substituted a number to "prove" this, I was a little surprised.
It's never possible to prove by numbers. Instead, use algebra!Here is the proof.(Original post by muh123)
Is Cosec^2(2x) - Cot^2(2x) = 1
Does the double angle thing affect the identity ??
,
From the identity,
So,
Last edited by raheem94; 07-04-2012 at 01:39. -
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Re: Trig questionNo, i am going to do chemical engineering at uni.(Original post by reallytired)
Well done! You intend to read maths at uni (I recall reading somewhere you are doing A-Levels ATM)?
If you want to know more about the subjects i am doing, have a look at my profile. -
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Re: Trig questionThanks for telling me about the typo, i have now corrected it.(Original post by reallytired)
Well done (apart from a slight typo)! You intend to read maths at uni (I recall reading somewhere you are doing A-Levels ATM)? -
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Re: Trig questionYeah I knew how to do the proof sorry I was just being really lazy. I was just getting confused because I was thinking to much but many thanks to Raheem94 who cleared it up. it was like 3 in the morning and I was trying to do maths It doesn't work when I'm tired LOL
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Re: Trig questionNo problem but time isn't an excuse, i haven't slept from the last 23hours!(Original post by muh123)
Yeah I knew how to do the proof sorry I was just being really lazy. I was just getting confused because I was thinking to much but many thanks to Raheem94 who cleared it up. it was like 3 in the morning and I was trying to do maths It doesn't work when I'm tired LOL
