calculus
posted by Anonymous .
solution for limit as delta x approaches 0 (1cos4x/1cos2x)

Usually the first step I take in doing a limit question is to actually substitute the approach value, so I got
lim cos 4x/(1 cos 2x) , as x >0
> 1/(10)
which is undefined,
so there is not limit, or the result is infinity
check: I tried x = .0001
and got 52631574.74 
however, a more careful reading reveals :)
lim (1cos4x)/(1cos2x)
= lim 4sin4x/2sin2x
= lim (4sin2x cos2x)/sin2x
= lim 4cos2x
= 4
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