式3: cosine left parenthesis, "x" plus "t" , right parenthesis left brace, "x" less than 2 pi , right bracecosx+tx<2π
3
式4: "y" less than or equal to cosine left parenthesis, "x" minus "t" , right parenthesis plus cosine left parenthesis, "x" plus "t" , right parenthesis left brace, "x" less than 2 pi , right bracey≤cosx−t+cosx+tx<2π
4
式5: "t" equals 2.8 8t=2.88
00
2 pi2π
5
式6: "x" greater than or equal to 2 pi left brace, "y" less than or equal to 3 , right bracex≥2πy≤3