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STEP Question integration by substitution

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Reply 20
Original post by TeeEm
just inverse cos in radians


But if this is for step and is radians I don't know how to do it without a calculator,should I learn arccos values etc. smh :?
Reply 21
Original post by Moordland
But if this is for step and is radians I don't know how to do it without a calculator,should I learn arccos values etc. smh :?


I see what the issue is

most definitely you must learn
Reply 22
Original post by TeeEm
I see what the issue is

most definitely you must learn


Thank you aha will do :smile:
Original post by Moordland
Thank you aha will do :smile:


If you are interested, it is because most of the (trigonometric) calculus is based on the fact that if x is small and in radians, then sin x is approximately equal to x. A proof is here https://www.youtube.com/watch?v=vz9_102nL8M, it is some very elegant and good maths.

With this, we can derive that d/dx (sin x) = cos x, and so on.
(edited 8 years ago)
Reply 24
Original post by Omghacklol
If you are interested, it is because most of the (trigonometric) calculus is based on the fact that if x is small and in radians, then sin x is approximately equal to x. A proof is here https://www.youtube.com/watch?v=vz9_102nL8M, it is some very elegant and good maths.

With this, we can derive that d/dx (sin x) = cos x, and so on.



Ah this makes sense!

I remember you, you were one of the good posters haha. Are you taking step 2+3 this year? :wink:
Original post by Moordland
Ah this makes sense!

I remember you, you were one of the good posters haha. Are you taking step 2+3 this year? :wink:


Haha I hate knowledge being thrown at you without any sense to it, hence why I was urged to clear it up for you.

I've just done step 1,2,3 and I'll be starting at Cam in October, would be more than happy to try and help you with arising problems (which there were numerous for me)
Reply 26
Original post by Omghacklol
Haha I hate knowledge being thrown at you without any sense to it, hence why I was urged to clear it up for you.

I've just done step 1,2,3 and I'll be starting at Cam in October, would be more than happy to try and help you with arising problems (which there were numerous for me)


Thank you.

Congratulations.
(edited 8 years ago)
Original post by Moordland
Thank you that seems nicer, may I ask why in radians is that by convention.


How long ago did you take your maths and FM A Levels?

Could you post questions in Maths rather than Maths Exams please?
Reply 28
Original post by Mr M
How long ago did you take your maths and FM A Levels?

Could you post questions in Maths rather than Maths Exams please?


Last year.

And sorry.

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