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anonymous
 4 years ago
lim > 0 sin(2x) /(x*cos(x) )
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anonymous
 4 years ago
lim > 0 sin(2x) /(x*cos(x) ) help

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anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0sin (2x) = 2sin(x)cos(x) so sin(2x) /(x*cos(x) =2sin(x)cos(x)/x*cos(x)=2sinx/x which as x>0 goes to 1

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0ups sry, forgot about 2 multuplying: lim 2sinx/x=2*1=2 x>0

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0sin (2x) can be written like: sin (2x) = 2sin(x)cos(x) substituting this expretion in the original one: sin(2x) /(x*cos(x) =2sin(x)cos(x)/x*cos(x)=2sinx/x taking limits, and noticing that lim as x>0 of sinx/x=1: lim 2sinx/x=2*1=2 x>0

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0dw:1352667129469:dw

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0why not? l'Hôpital rule

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0yes, using l'hospital's rule works

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Don't break your head ! You know that sin(x)=x as x tends to zero. So sin(2x) = 2x. In the denominator, keep x as it is and cos(x)=1. Hence the answer

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0thanks, but the image is ok?

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0dw:1352669528245:dw

lopus
 4 years ago
Best ResponseYou've already chosen the best response.1claro que es posible es solamente derivar arriba y abajo como lo muestras en la imagen y ya
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