please help!!!!!!!!!!!! Will mark brainliest

Answer:
○ [tex]\displaystyle 3 ≤ f(x) ≤ 5[/tex]
Step-by-step explanation:
All you do is plug 12 and 4 into the equation to get the range of quantities:
[tex]\displaystyle \boxed{5} = \sqrt{2[12] + 1} \\ \boxed{3} = \sqrt{2[4] + 1} \\ \\ \boxed{\boxed{3 ≤ f(x) ≤ 5}}[/tex]
I am joyous to assist you at any time.