Does Taylor Series accurately represent limits in calculus?

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ironman
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Homework Statement


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lim x -> 0
Fraction with numerator e^(3x) - sin(x) - cos(x) + ln(1 - 2x) and denominator -1 + cos(5x).


2. Homework Equations

Taylor series for sin cos e and ln ()

The Attempt at a Solution


I tried expanding the sine to 3-degree, and everything else 2-degree. I ended up with this:

Handwritten fraction: numerator is 1/2 + (1/6)x + 1/2 - 2, denominator is -25/2.

Now the problem is that WolframAlpha says it should be -6/25. Now if only that -2 were +2...
 
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I got the answer! the first 1/2 (expansion from e^3x) is supposed to be 4 1/2 not 1/2, because you get (3x)^2 / 2! not (x)^2/2!