Hi, I have a question regarding the envelope function in parameter representation.
Let an array of curves in cartesian coordinates be given in parameter representation, with curve parameter ๐ก and array variable ๐
๐ฅ=๐ฅ(๐ก,๐)
๐ฆ=๐ฆ(๐ก,๐)
Condition for envelope is:
๐/๐๐ก ๐ฅ(๐ก,๐) ๐/๐๐ ๐ฆ(๐ก,๐)=๐/๐๐...