2.6.3 test (cst): functions and relations
which of the following statements are not true regarding functions?
the vertical line test may be used to determine whether a
function is one-to-one.
b. a function is a relation in which each value of the input variable is
paired with at least one value of the output variable.
the horizontal line test may be used to determine whether a
function is one-to-one.
d. a sequence is a function whose domain is the set of natural
numbers.