Prove the Identity sec2 x cot x cot x tan x Note that each
     Prove the Identity.  sec^2 x cot x - cot x - tan x  Note that each Statement must be based on a Rule chosen from the Rule menu. To question mark.   
  
  Solution
You need to show the options for the rule
sec^2xcotx - cotx = tanx
LHS : cotx( sec^2x -1 )
Use the identity : 1+ tan^2x = sec^2x
So, LHS : cotx ( tan^2x)
Now Use the formula : tanx = 1/cotx
So, LHS : tan^2x/tanx
tanx
RHS

