differentiate y=1/In(x)

y = 1/ln(x)

 

y = ln(x)^-1

 

dy/dx = -ln(x)^-2*(dln(x)/dx)

 

Now dlnx)/dx = 1/x so dy/dx = -ln(x)^-2/x  or  dy/dx = -1/(x*ln(x)^2)

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