问答题
y=(C1+C2x)e2x,y|x=0,y′|x=0=1;
问答题y=(C1+C2x)e2x,y|x=0,y′|x=0=1;
x2-y2=C,y|x=0=5;
问答题x2-y2=C,y|x=0=5;
求数列的最大项