How do you implicitly differentiate #-3=xsecy#?

1 Answer
Jul 21, 2016

#(dy)/(dx)=-xcoty#

Explanation:

When we implicitly differentiate a function #f(y)#, we first differentiate #f(y)# with respect to #y# and then multiply by #(dy)/(dx)#. This comes from chain rule as #(df)/(dx)=(df)/(dy)xx(dy)/(dx)#.

Now using product rule for differentiating #3=xsecy#, we get

#0=x xxsecy+1xxsecytany(dy)/(dx)# or

#secytany(dy)/(dx)=-xsecy# or

#(dy)/(dx)=(-xsecy)/(secytany)#

= #(-xcancel(secy))/(cancel(secy)tany)#

= #-xcoty#