FUNCTIONS 7

Question

 

Determine the domain sqrt. of (x-4) > or equal to 0.

a. [–4, ∞)

b. (∞, –2]

c. (–∞,∞)

d. [4, ∞)

Which of the following is not a one-to-one function?

Select one:

a. f(x) = x+ 4
b. f(x) = 1/5 (x+4)^3

c. f(x) = –4x

d. f(x) = x² + 4

 

Answer 1

1)

Sqrt. of (x-4) > or equal to 0.

 

Negative square root is not possible.

 Sqrt(x-4) ≥ 0 then x ≥ 4

So the domain is [4,∞]

Option D is correct.

 

2)

Draw the graph for f(x) = x² +4

Observe that f(-3) =f(3)

So it is not a one to one function

Option D is correct.