· Respond to your classmates’ posts. Is their work similar to your own? Did they use the vocabulary words correctly? Do you understand their answers?

PEERS POST:

Hello Class & Professor,

The rational expression I was assigned to complete was #29 in this week’s discussion. The domain of any algebraic expression on one variable is that set of all the real numbers which can be used in place of that variable. Any real number that causes the denominator to be zero must not be included in the domain in rational expressions

1.) I need to factor the denominator to find the domain of my first rational expression, so I will need to find the excluded values.

x 2 – 7x + 12

5x

The first thing I need to do is set up my expression.

5x=0

Dividing both sides by 5

5x/5 = 0/5

X= 0

X = 0 This is the excluded value from the first equation.

I chose to make the set of all Reals excluding x=0 (D) of my first expression. To write it in set notation, this can be written as D = {x} x ? ?, x ? 0}

2.) Similar to my first rational expression, I use the same method for my second rational expression.

w2 – 9w – 36

16w2 – 1

In order to find my excluded values for w, I need to set my second expression’s denominator to zero.

16w 2 -1 = 0 This is the difference of squares, which I can factor.

(4w-1)(4w+1) = 0 After that, I set each factor to equal zero

4w-1 = 0 or 4w+1 = 0 Add or subtract 1 from both sides

4w = 1 or 4w = -1 Then divide both sides by 4

W=1/4 or w=-1/4 These are the excluded values of the second equation.

My second expression (D) takes into account the set of all Real numbers that exclude ±1/4. As a set notation, this can be written as D = {w| w ? ?, w ? ±1/4}

-Chiquita