表达式4: left brace, "x" less than or equal to 0 : "x" plus 4 , "x" greater than 0 : left parenthesis, "x" minus 3 , right parenthesis squared , right bracex≤0:x+4,x>0:x−32
4
Infinite discontinuity
5
表达式6: negative StartFraction, 1 Over "x" minus 6 , EndFraction plus 3−1x−6+3
