may i know is it lim x to 0 (1/sinx - 1/x ) is equals to infinity??
You cannot apply L'Hospital on this function (yet), you'd need to rewrite it so that you get something of the form 0/0 or ∞/∞.
To apply L'Hospital's Rule, put the expression in theform f(x)/g(x). If the form is indeterminate, then you can apply the Rule.
Just to avoid confusion: it has to be 0/0 or ∞/∞ as I said, since there are more indeterminate forms possible. Many can be reduced to one of the two 'allowed' ones to use the rule though.
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