Write a polynomial function in standard form with the given roots: -4i

Step-by-step explanation:

By the conjugate rule, if -4i is a root, then so is +4i.  So we have 2 roots, thus, we have a second degree polynomial (namely, a quadratic).  If

x = -4i, then

x + 4i is a root.

If

x = 4i, then

x - 4i is a root.  

Having (x - 4i)(x + 4i) as roots, we can now FOIL them together to get a polynomial of least degree.

FOILing gives us

Notice that the +4ix and the -4ix cancel each other out, leaving you with

Since

we can make the substitution:

which simplifies to

In function notation form:

step-by-step explanation:

20% of 120 is 24. if you subtract 24 from 120 you get 96

hello from mrbilldoesmath!

answer:

the domain is the set { -2, 0, 2, 3}

discussion:

the domain is the set of x values in the ordered pairs (x,y). taking the x, or first component, of each ordered pair gives   -2, 0, 2, 3.

you,

mrb