Find limits of sine and cosine functions

Glissando
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Homework Statement


Find the limit:

lim (1-cos2x)/(xsinx)
x->0


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The Attempt at a Solution



I've done this over and over and over again! The answer is supposed to be 0 but I keep getting 2 ):

lim (1-cos2x)/(xsinx)
x->0

lim (1-1+2sin2x)/(xsinx)
x->0

lim (2sin2x)/(xsinx)
x->0

lim (2sinx)/x
x->0

= 2*1 = 2

Any help is appreciated! Thank you!
 
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I don't see anything wrong with what you did. I'd say the limit is 2 as well.
 
Thanks guys (: I guess textbook error then! Yay!

Thank you <3
 
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