Question

函数y=(2x-1)/(x+1)的定义域为{x|x≠ -1},值域为{y|y≠2},这个值域怎么算?

Answer 1

y=(2x－1)/(x＋1)

=[2(x＋1)－3]/(x＋1)

=2－3/(x＋1)

因3/(x＋1)≠0,则值域是{y|y≠2}