Question

I can’t figure out the answer to this, does anybody know?

Answer 1

Answer:

Option (2).

Step-by-step explanation:

Let f(x) and g(x) are the two functions with domain A and B.

Then (fg)(x) will be the function with domain A∩B

(fg)(x) = f(x)g(x)   Domain : A∩B

In this question two functions are,

c(x) = $\frac{5}{(x-2)}$ and d(x) = (x + 3)

Domain : (x - 2) > 0 ⇒ x > 2

              and (x - 2) < 0 ⇒ x < 2

Or domain of (cd)(x) will be C = (-∞, 2)∪(2, ∞).

Similarly, d(x) = x + 3

Domain : All real numbers

             : D = (-∞, ∞)

(cd)(x) = c(x)d(x)

          = $\frac{5}{(x-2)}\times (x+3)$

Domain of (cd)(x) will be,

Domain : C∩D = (-∞, 2)∪(2, ∞) ∩ (-∞, ∞)

             : (-∞, 2) ∩ (2, ∞)

Therefore, domain of (cd)(x) will be all real values except 2.

Option (2) will be the answer.