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**b00yeah05** a) $\displaystyle f(x)=1/sin(x)$

b) $\displaystyle g(x)= ln(x^2)$

find the derivitives....just need to confirm.

i have worked through the questions and i for a) i get $\displaystyle (-cos(x))/sin(x)^2$ by using the quotient rule. Mr F says: Correct.

but when i try differentiate on a computer software i get $\displaystyle -1/sin(x)^2*cos(x)$....are they the same???? Mr F says: Yes. $\displaystyle -\frac{1}{\sin^2 x} \times \cos x = -\frac{\cos x}{\sin^2 x}$.

and for the second one i know that the answer is $\displaystyle 2/x$since ln(x) = 1/x. but not sure how to show the working...any help would be appreciated.

thanks