Select the correct answer.

What is the value of [tex]\( g(2) \)[/tex]?

[tex]\[ g(x) = \begin{cases}
\left(\frac{1}{2}\right)^{x-3} & \text{if } x \ \textless \ 2 \\
x^3 - 9x^2 + 27x - 25 & \text{if } x \geq 2
\end{cases} \][/tex]

A. -1
B. 1
C. 2
D. [tex]\(\frac{1}{2}\)[/tex]



Answer :

To determine the value of [tex]\( g(2) \)[/tex], we need to apply the definition of the function [tex]\( g(x) \)[/tex] for [tex]\( x = 2 \)[/tex].

Given the piecewise definition of [tex]\( g(x) \)[/tex]:
[tex]\[ g(x)=\left\{ \begin{array}{ll} \left(\frac{1}{2}\right)^{x-3} & \text{if } x<2 \\ x^3-9x^2+27x-25 & \text{if } x \geq 2 \end{array} \right. \][/tex]

Since [tex]\( x = 2 \)[/tex] falls in the category where [tex]\( x \geq 2 \)[/tex], we should use the second part of the piecewise function:
[tex]\[ g(x) = x^3 - 9x^2 + 27x - 25 \][/tex]

Next, substitute [tex]\( x = 2 \)[/tex] into the function:
[tex]\[ g(2) = 2^3 - 9 \cdot 2^2 + 27 \cdot 2 - 25 \][/tex]

Calculating each term individually:
[tex]\[ 2^3 = 8 \][/tex]
[tex]\[ 9 \cdot 2^2 = 9 \cdot 4 = 36 \][/tex]
[tex]\[ 27 \cdot 2 = 54 \][/tex]
So, substituting these values in the expression we get:
[tex]\[ g(2) = 8 - 36 + 54 - 25 \][/tex]

Now, we simplify the expression by performing the arithmetic operations:
[tex]\[ g(2) = 8 - 36 = -28 \][/tex]
[tex]\[ -28 + 54 = 26 \][/tex]
[tex]\[ 26 - 25 = 1 \][/tex]

Therefore, the value of [tex]\( g(2) \)[/tex] is:
[tex]\[ \boxed{1} \][/tex]

Thus, the correct answer is:
[tex]\[ \text{B. } 1 \][/tex]

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