表达式1: left parenthesis, StartFraction, 2 "t" Over 1 plus "t" squared , EndFraction , StartFraction, "t" squared minus 1 Over 1 plus "t" squared , EndFraction , right parenthesis left parenthesis, 1 minus "s" , right parenthesis plus "s" left parenthesis, "t" , sin left parenthesis, "t" , right parenthesis , right parenthesis 有图表。2t1+t2,t2−11+t21−s+st,sint
定义域t最小值： negative 100−100
less than or equal to "t" less than or equal to≤t≤
