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anonymous
 3 years ago
Integral with trig functions
anonymous
 3 years ago
Integral with trig functions

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anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0dw:1361089150658:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0dw:1361089181888:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0or would it be cos^xcos5x

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0no cant combine them...it would just be \[\cos(5x)  \cos^{2} x \cos(5x)\]

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0so left integral is easy

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0hmm no i cant do that

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0that 5x is just blowing my mind

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0yeah im not sure of way to do it without expanding out the cos(5x) ..... which would be messy

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.2huh ? integral of cos 5x is just sin 5x/5 +c .

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0dw:1361089595564:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0yA i know that integral, but its the cos^2 that is messin me up

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.2ok, you need to used \(\sin^2x = (1 \cos2x )/2\)

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.2then, for cos 2x cos 7x there is a standard formula for , cos A cos B =...

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0ahh i always forget sum to product rules ... anyway, here is solution http://www.wolframalpha.com/input/?i=integrate+sin^2%28x%29+cos%285x%29+dx

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0dw:1361090139384:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0ok so here is another, im thinking with this one i can multiply by a 1/2 and use the identity sin2x

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.2sin x cos x = (sin 2x) /2 then we have formula for sin A cos B

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0dw:1361090244648:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0for the first question by parts can also be used . \[\Large \frac{1}{5}\sin^2(x)\sin(5x)\frac{2}{5}\int\limits \sin(x)\sin(5x)\cos(x)dx\]

.Sam.
 3 years ago
Best ResponseYou've already chosen the best response.0\[( \sin A ) ( \sin B )=\frac{1}{2} (\cos (A B )\cos (A +B ))\]

.Sam.
 3 years ago
Best ResponseYou've already chosen the best response.0But there's still a lot of work if you do this

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0dw:1361090429038:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0dw:1361090501054:dw

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.2why  *minus* in between ?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0integral of sin is cosx

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.2both of  from that you have factored out, right ? to make 1/4 ?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0well, before i took integral

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0dw:1361090806081:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0those will both be negative right?

hartnn
 3 years ago
Best ResponseYou've already chosen the best response.2integral of those will be negative, yes, right.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0ok thats all i got, thank you so much both of you for helping me out, big test this friday
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