The vertex of a parabola is at the point (3,1), and its focus is at (3,5). what function does the graph represent?
a. f(1) = 1/16(x – 3)^2 - 1
b. f(t)= 1/4(x + 3)^2 – 1
c. f(x)=1/4(x – 3)^2 - 1
d. f(x) = 1/16(x – 3)^2 + 1

1- is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis. 2- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis. 3- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in part b?