- #1
idris
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Hey guys, have a questions about L'Hopital and arcsin.
The question is to find the limit of (arcsin(2x))/x^3 as x->0. I can find the limit no problem just by applying L'Hopital, but I am having difficulty proving that it's valid to use L'Hopital with the function, because with f(x)=arcsin(2x), the limit of arcsin(2x) as x->0 is 2x, rather than 0 or infinity as is required. I think I may have to express arcsin(2x) as a ratio and then apply L'Hopital again, but I can't figure out how to do that. Thanks for any help!
The question is to find the limit of (arcsin(2x))/x^3 as x->0. I can find the limit no problem just by applying L'Hopital, but I am having difficulty proving that it's valid to use L'Hopital with the function, because with f(x)=arcsin(2x), the limit of arcsin(2x) as x->0 is 2x, rather than 0 or infinity as is required. I think I may have to express arcsin(2x) as a ratio and then apply L'Hopital again, but I can't figure out how to do that. Thanks for any help!
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