What is a rational zero?

1 Answer
Dec 28, 2015

Answer:

A rational zero of a polynomial #f(x)# in a variable #x# is a fraction #p/q# such that #f(p/q) = 0# where #p# and #q# are integers.

Explanation:

A rational number is a number that can be expressed in the form #p/q# for some integers #p# and #q#.

A zero of an expression #f(x)# is a value of #x# such that #f(x) = 0#.

So a rational zero of an expression #f(x)# is basically a fraction #p/q# such that #f(p/q) = 0#.

For example, #2x^2-3x-5# has rational zeros #x=-1# and #x=5/2#, since substituting either of these values for #x# in the expression results in the value #0#.