Calculus question. Integral and substitution @zepdrix
Oh this silly problem :) lol ya i remember this
It's good that they gave you the multiplication step, because that's not something you can easily come up with on your own. It's a messy trick to making this one work.
\[\large\rm \int\limits \csc x\left(\frac{\csc x+\cot x}{\csc x+\cot x}\right)dx=\int\limits\frac{\csc x(\csc x+\cot x)}{\csc x+\cot x}dx\]You understand that only the numerator is getting this cscx, ya? :)
Is this correct? so far
Oooo no no no, let's not do sines and cosines :OO It might be right, but uhhh boy that's a lot of extra work
ok, lol. What's your method?
...
du = (-csc x cot x) + (sec x tan x), yes?
oh, then du = (-csc x cot x) + sec^2 x
@zepdrix is that ok?
heck i ruined \[\csc x \times \frac{ \csc x - \cot x }{ \csc x - \cot x }\]
???
Well first multiply out your numerator so you have an idea of what's going on.\[\large\rm =\int\limits \frac{\csc x \cot x+\csc^2x}{\csc x+ \cot x}dx\]What you're doing is, you're letting your denominator =u, and something magical happens :)
Ah, I think I see where you're getting @zepdrix
@StudyGurl14 just an alternate method so u will have \[\int\limits\frac{ \csc x (\csc x - \cot x) }{ \csc x - \cot x } dx\]
du/dx = \(\Large -\csc x \cot x - (-\csc^2 x)=-\csc x \cot x + csc^2 x\)
Wait, hold on
Made a mistake there
Woops, we're using csc x + cot x for our u, right? :O You silly billy
du/dx = \(\Large -\csc x \tan x + \csc^2 x\) So dx = \(\Large\frac{1}{-\csc x \tan x + \csc^2 x}\) yea?
tack on a du at the end
cot x --> -csc^2x, right?
\[\csc x - \cot x = u\] so \[du = (-\csc x \cot x + \csc^2 x) dx\]
ugh, I keep doing that lol. Yeah
So that'd be negative, then you pull out the -1, and it changes to |dw:1453498357930:dw|
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