Name: Lorraine

Who is asking: Student
Level: Secondary

Question:
The question asks me to find the value of the variable that must be excluded in each rational expressionion. The operation is:

   a
______
 a - 2

How do I work this out?

Hi Lorraine,

I like your use of the word operation because that is the way I think of a/(a-2). a/(a-2) is the number that results from the operation of dividing the number a by the number a-2. The difficulty here is that the operation of division doesn't work if you attempt to divide by zero. Thus the values of a that you have to exclude are any values that make the denominater zero. That is values of a that make a  - 2 = 0. There is only one such a and that is a = 2.

Cheers
Harley