Answer:
see explanation
Step-by-step explanation:
Using the trigonometric identities
cot A =
, tanA =
, cscA =
, secA = 
Consider the right side

= 
= 
=
× sinAcosA ( cancel sinAcosA )
= cos²A - sin²A
= cos2A
= left side ⇒ verified
What parameter should be set to none, in the View Properties dialog, if you do not want to see the walls from the floor below? Use the Temporary Hide/Isolate tool to get a better look at your model.
So beacause the VAT costsnyou need to move the variable to the left then consider and then thr rate will turn to 0%