I am reviewing for my midterm and realize that I was out sick when the class covered trigonometric functions. Any explanation on how to solve these would be great!

-limx->0 (x/arcsinx)

-limx->infinity (xarccotx)

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- February 1st 2010, 07:06 PMamm345Limits Involving Trigonometric Functions
I am reviewing for my midterm and realize that I was out sick when the class covered trigonometric functions. Any explanation on how to solve these would be great!

-limx->0 (x/arcsinx)

-limx->infinity (xarccotx) - February 1st 2010, 07:08 PMDrexel28
- February 1st 2010, 07:37 PMPulock2009
how about using L'Hospital's rule? that makes it a lot easier. by the way wats the answer.is the first one =1???

- February 1st 2010, 07:38 PMamm345
I thought the first one was 0? and I already tried L'Hopitals and I still couldn't figure out.

- February 1st 2010, 07:42 PMPulock2009
u need to differentiate the numerator and the denominator separately.then the numerator becomes 1.and the denominator becomes 1/sqrt(1-x^2).now put the limits and u should get 1.

- February 1st 2010, 07:44 PMamm345
How about when I can't do it seperately?

Like for limx->0 x/arccosx? - February 1st 2010, 07:51 PMPulock2009
i donot get the second one. limit doesnot exist for the second one unless x->0.

- February 1st 2010, 07:52 PMamm345
x does tend to 0, isn't the limit equal to 0?

- February 1st 2010, 07:57 PMPulock2009
no. limit for the second one is also 1.provided ,ofcourse,if x->0.

- February 1st 2010, 07:59 PMPulock2009
u must learn your differentiation formulas well.:D