Expression 4: left parenthesis, "x" minus StartFraction, 3 pi Over 4 , EndFraction , right parenthesis squared plus left parenthesis, "y" , right parenthesis squared minus left parenthesis, "z" , right parenthesis squared equals "t" left brace, negative 2sin left parenthesis, "k" minus pi , right parenthesis less than "z" less than 2sin left parenthesis, "k" minus pi , right parenthesis , right bracex−3π42+y2−z2=t−2sink−π<z<2sink−π
