Question

Please help. don’t understand :((

Answer 1

f(19) = -
`(27)/(7)`

Explanation:

Given

f(x) =
`(3)/(x+2)` -
`√(x-3)`

To evaluate f(19), substitute x = 19 into f(x) , that is

f(19) =
`(3)/(19+2)` -
`√(19-3)`

=
`(3)/(21)` -
`√(16)`

=
`(1)/(7)` - 4

=
`(1)/(7)` -
`(28)/(7)`

= -
`(27)/(7)`

Answer 2

Explanation:

place x = 19

f(19) = 3 / 19 + 2 - Sqrt 21 - 3

= 3/21 - 4

= - 81/21

= - 27/7