表达式2: cosine left parenthesis, "x" , right parenthesiscosx
2
表达式3: StartFraction, tan left parenthesis, "x" , right parenthesis Over StartRoot, 1 plus tan squared left parenthesis, "x" , right parenthesis , EndRoot , EndFractiontanx1+tan2x
3
表达式4: sine left parenthesis, "x" , right parenthesissinx