13. write a function with a zero of 1/2. explain how you know.

The function is  

Step-by-step explanation:

If a function has a zero of .

The we can write  .

We need to work backwards to obtain the function:

We multiply through by 2 to get:

.

This implies that:

Hence a function with such zero is  

do it yourself this is easy

step-by-step explanation:

step-by-step explanation:

we have

using a graphing tool

see the attached figure

this is a quadratic equation (vertical parabola) open up

the vertex is a > vertex

the domain of the function is all real > interval (-∞,∞)

the range of the function is the > [-6.125,∞)

the function has two x->   and

the function is increasing over the > (0.25,∞)

the function is decreasing over the > (-∞,0.25)