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I was doing a question on differentiate parametric equations which has this result [tex]\frac{dy}{dx}=\frac{4sin(4\theta)}{sin\theta}[/tex]. it then asks what the value of [tex]\frac{dy}{dx}[/tex]would be if [tex]\theta=0[/tex]. if I substitute [tex]\theta=0[/tex] into [tex]\frac{4sin(4\theta)}{sin\theta}[/tex] than I get [tex]\frac{0}{0}[/tex] which I persume would be infinity, i.e. the grdient of the graph at that point is undefinined. but if I transform [tex]\frac{4sin(4\theta)}{sin\theta}[/tex] into [tex]16cos\theta cos(4\theta)[/tex] and substitute[tex]\theta=0[/tex] in than I got 16 which is the correct answer. How can this be possible?

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# Probability question help needed please

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