表达式2: "g" left parenthesis, "x" , right parenthesis equals co tangent left parenthesis, "x" , right parenthesis minus "x" co secant squared left parenthesis, "x" , right parenthesisgx=cotx−xcsc2x
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表达式3: "h" left parenthesis, "x" , right parenthesis equals 2 "x" co tangent left parenthesis, "x" , right parenthesis co secant squared left parenthesis, "x" , right parenthesis minus 2 co secant squared left parenthesis, "x" , right parenthesishx=2xcotxcsc2x−2csc2x