Of the functions listed, which one decreases over the following interval (2, infinity)?

Question

Answer choices:

1. y = √x+5-3
2. y = - √x+5 + 5
3. y = √x-2 + 1
4. y = - √x-2 - 5

Answer 1

:

1.  y = √x+ 5 -3
2. y = - √x+5 + 5
3. y = √x-2 + 1
4. y = - √x-2 - 5

It can not be no.1 because this function will increase when x value increase.

It can not be no.3 because this function also increase with x.

For functions 2 & 4 both of them will decrease as x increase because they have negative sign in front of the first term.( you have negative slope).