Quote (saber_x3 @ Sep 12 2014 06:58pm)

Ya, so it's giving you the correct answers, just negative
that is because you got b as 10^8 when it is -10^8
10^-8 is essentially 0
you can make matlab format it to show more zeros, but i don't remember how

matlab is matrix laboratory, and it expresses some answers as (constant*matrix)
it can help when you have a large matrix with large numbers

Quote (saber_x3 @ Sep 12 2014 08:56pm)

Well...change b to -
you input b incorrectly

Quote (saber_x3 @ Sep 12 2014 11:00pm)

what it becomes isnt really your worry in programming. intro programming usually has complex expression that test your orderof operations and paraenthesis knowledge. you will see many equations that you might not understand. but, it is xx/2 due to expansion of the series

Quote (TheDiablo3KnowItAll @ Sep 12 2014 09:13pm)

Ooh, so it only took the first 2 nonzero terms of the taylor expansion right?

Quote (TheDiablo3KnowItAll @ Sep 12 2014 10:45pm)

whats the main cause of this error? is it because your chopping off the taylor series at 2 terms ??

Quote (saber_x3 @ Sep 13 2014 01:15am)

I plugged it in wolfram alpha and it's actually the first non zero term only
pretty sure the error is from using that first term only
i don't believe there is any significant error from matlab even on  x=10^-9

Quote (TheDiablo3KnowItAll @ Sep 13 2014 12:40am)

why is it the first nonzero term only?

the cos x series goes like this.. 1 - x^2/2! + x^4/4! - x^6/6! + ...

and the expression was 1 - cos x and it approached x^2/2!.

So 1 - (1 - x^2/2!) = x^2/2!