表达式2: "y" equals natural log left parenthesis, StartFraction, 1 Over cos left parenthesis, "x" , right parenthesis , EndFraction , right parenthesisy=ln1cosx
2
表达式3: "y" equals "x" squaredy=x2
3
表达式4: "x" equals StartFraction, pi Over 3 , EndFractionx=π3