Evaluate the function for the indicated values.
$f ( x ) = 2 \llbracket x + 6 \rrbracket + 8$
(i) $f ( - 1 )$
(ii) $f ( - 2.3 )$
(iii) $f \left( \frac { 2 } { 3 } \right)$
A) $\begin{array} { l l l } \text { (i) } 19 & \text { (ii) } 14 & \text { (iii) } 20 \end{array}$
B) $\begin{array} { l l l } \text { (i) } 18 & \text { (ii) } 16 & \text { (iii) } 20 \end{array}$
C) $\begin{array} { l l l } \text { (i) } 19 & \text { (ii) } 14 & \text { (iii) } 22 \end{array}$
D) $\begin{array} { l l l } \text { (i) } 18 & \text { (ii) } 16 & \text { (iii) } 22 \end{array}$
E) $\begin{array} { l l l } \text { (i) } 18 & \text { (ii) } 14 & \text { (iii) } 20 \end{array}$

Question

Evaluate the function for the indicated values. 
$f ( x ) = 2 \llbracket x + 6 \rrbracket + 8$
(i) $f ( - 1 )$
(ii) $f ( - 2.3 )$
(iii) $f \left( \frac { 2 } { 3 } \right)$
A) $\begin{array} { l l l } \text { (i) } 19 & \text { (ii) } 14 & \text { (iii) } 20 \end{array}$
B) $\begin{array} { l l l } \text { (i) } 18 & \text { (ii) } 16 & \text { (iii) } 20 \end{array}$
C) $\begin{array} { l l l } \text { (i) } 19 & \text { (ii) } 14 & \text { (iii) } 22 \end{array}$
D) $\begin{array} { l l l } \text { (i) } 18 & \text { (ii) } 16 & \text { (iii) } 22 \end{array}$
E) $\begin{array} { l l l } \text { (i) } 18 & \text { (ii) } 14 & \text { (iii) } 20 \end{array}$

Quizplus · Accepted Answer

The function uses the floor function $\llbracket x \rrbracket$. For (i) $-1 + 6 = 5$, $\llbracket 5 \rrbracket = 5$, so $f(-1) = 2(5) + 8 = 18$. For (ii) $-2.3 + 6 = 3.7$, $\llbracket 3.7 \rrbracket = 3$, so $f(-2.3) = 2(3) + 8 = 14$. For (iii) $\frac{2}{3} + 6 = 6.666...$, $\llbracket 6.666... \rrbracket = 6$, so $f\left(\frac{2}{3}\right) = 2(6) + 8 = 20$.

Evaluate the Function for the Indicated Values f(x)=2⟦x+6⟧+8f ( x ) = 2 \llbracket x + 6 \rrbracket + 8f(x)=2[[x+6]]+8

Evaluate the Function for the Indicated Values $f ( x ) = 2 \llbracket x + 6 \rrbracket + 8$