The Student Room Group

a level quotient rule…again

i got this far…i feel like i’m so close yet so far

https://imgur.com/a/VwCmHYb
(edited 1 month ago)
Reply 1
Original post by esha06
i got this far…i feel like i’m so close yet so far
https://imgur.com/a/VwCmHYb

You cant just cancel one of the terms on the numerator. But you have cos^2 + sin^2 on the numerator and pythagoras would be turning in his grave if you didnt ...
Reply 2
Original post by mqb2766
You cant just cancel one of the terms on the numerator. But you have cos^2 + sin^2 on the numerator and pythagoras would be turning in his grave if you didnt ...
omggggg i didn’t even notice that 😅😅😅😅
Reply 3
Original post by esha06
i got this far…i feel like i’m so close yet so far
https://imgur.com/a/VwCmHYb

A very easy way to do quotient rule if you're struggling with it is to make the term (in this instance) cos(2x)[1+sin(2x)]^-1 and then do a product rule on it with chain rule (e.g becoming [2sin(2x)]/[1+sin(2x)] - [2cos^2(2x)]/[1+sin(2x)]^2). You can simplify further if needed.
Original post by esha06
i got this far…i feel like i’m so close yet so far
https://imgur.com/a/VwCmHYb

Hi i did this as well and wanted to check i got the right answer. Did you get 2 as the numerator?
Reply 5
Original post by aamina.hs
Hi i did this as well and wanted to check i got the right answer. Did you get 2 as the numerator?
this is the mark scheme it’s acc -2

https://imgur.com/a/YbfARTG
Original post by esha06
this is the mark scheme it’s acc -2
https://imgur.com/a/YbfARTG

oh yeah sorry i put the minus in front of the fraction thank you!!
Original post by Muttley79
Don't post solutions - it's not allowed - edit!

That's not the solution, it just shows what he already showed in (https://imgur.com/a/VwCmHYb line 5)
but you can better see the use of s^2+c^2=1 (which someone else already mentioned here) to simplify further.
(edited 1 month ago)
Original post by math-path
That's not the solution, it just shows what he already showed in (https://imgur.com/a/VwCmHYb line 5)
but you can better see the use of s^2+c^2=1 (which someone else already mentioned here) to simplify further.

You should not be posting detail - just hints - read the rules
Original post by Muttley79
You should not be posting detail - just hints - read the rules

The rules states and I quote:
"Offer hints to guide the student. Full solutions will normally be removed."
You can certainly post details as long as it is not the full solution. What I provided was already mentioned just better organized to see where to use that identity.
(edited 1 month ago)
Original post by math-path
The rules states and I quote:
"Offer hints to guide the student. Full solutions will normally be removed."
You can certainly post details as long as it is not the full solution. What I provided was already mentioned just better organized to see where to use that identity.

A hint is a verbal comment not a copied section of the solution. Remove please.
(edited 1 month ago)
Reply 11
Original post by Muttley79
A hint is a verbal comment not a copied section of the solution. Remove please.
i don’t think he meant it as a copy he just meant it as a correction of my working out
the guy before him basically said the same thing this guy just actually wrote it out
Original post by esha06
i don’t think he meant it as a copy he just meant it as a correction of my working out
the guy before him basically said the same thing this guy just actually wrote it out

Yes the first post was OK posting part of the solution ike this isn't - you could look up the answer yourself and there is no explanation to further your understanding.

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