Answer:
Answers are a. 8, b. 10, c. -2, d. invalid
Step-by-step explanation:
a.
[tex]f(x)=|x|\\So, f(8)=|8|=8\,;[Modulus\,\,is\,\,always\,\,the\,\,positive\,\,value][/tex]
b.
[tex]f(x)=3^x+1\\f(2)=3^2+1=9+1=10[/tex]
c.
[tex]f(k)=\frac{k}{2}+1\\f(-6)=\frac{-6}{2}+1=-3+1=-2[/tex]
d.
[tex]f(x)=\sqrt{x-5} \\f(3)=\sqrt{3-5}=\sqrt{-2}\\There\,\,is\,\,no\,\,real\,\,solution\,\,for\,\,root\,\,of\,\,a\,\,negative\,\,number[/tex]
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