Suppose that the functions [tex]\( f \)[/tex] and [tex]\( g \)[/tex] are defined for all real numbers [tex]\( x \)[/tex] as follows:
[tex]\[
\begin{array}{l}
f(x) = 2x - 4 \\
g(x) = x - 3
\end{array}
\][/tex]

Write the expressions for [tex]\( (f \cdot g)(x) \)[/tex] and [tex]\( (f+g)(x) \)[/tex], and evaluate [tex]\( (f - g)(1) \)[/tex].

[tex]\[
\begin{array}{c}
(f \cdot g)(x) = \square \\
(f+g)(x) = \square \\
(f-g)(1) = \square
\end{array}
\][/tex]



Answer :

Certainly! Let's solve this problem step-by-step.

1. Finding [tex]\((f \cdot g)(x)\)[/tex]:

The expression [tex]\( (f \cdot g)(x) \)[/tex] represents the product of the functions [tex]\( f(x) \)[/tex] and [tex]\( g(x) \)[/tex].
[tex]\[ f(x) = 2x - 4 \][/tex]
[tex]\[ g(x) = x - 3 \][/tex]
Therefore,
[tex]\[ (f \cdot g)(x) = f(x) \cdot g(x) = (2x - 4)(x - 3) \][/tex]
To simplify this, we expand the product:
[tex]\[ (2x - 4)(x - 3) = 2x \cdot x + 2x \cdot (-3) - 4 \cdot x - 4 \cdot (-3) \][/tex]
[tex]\[ = 2x^2 - 6x - 4x + 12 \][/tex]
Combine like terms:
[tex]\[ = 2x^2 - 10x + 12 \][/tex]
So,
[tex]\[ (f \cdot g)(x) = 2x^2 - 10x + 12 \][/tex]

2. Finding [tex]\((f+g)(x)\)[/tex]:

The expression [tex]\( (f + g)(x) \)[/tex] represents the sum of the functions [tex]\( f(x) \)[/tex] and [tex]\( g(x) \)[/tex].
[tex]\[ f(x) = 2x - 4 \][/tex]
[tex]\[ g(x) = x - 3 \][/tex]
Therefore,
[tex]\[ (f + g)(x) = f(x) + g(x) = (2x - 4) + (x - 3) \][/tex]
To simplify this, combine like terms:
[tex]\[ = 2x + x - 4 - 3 \][/tex]
[tex]\[ = 3x - 7 \][/tex]
So,
[tex]\[ (f + g)(x) = 3x - 7 \][/tex]

3. Evaluating [tex]\((f - g)(1)\)[/tex]:

The expression [tex]\( (f - g)(x) \)[/tex] represents the difference of the functions [tex]\( f(x) \)[/tex] and [tex]\( g(x) \)[/tex].
So, we need to find [tex]\( (f - g)(1) \)[/tex]. First, let's find [tex]\( f(1) \)[/tex] and [tex]\( g(1) \)[/tex].
[tex]\[ f(x) = 2x - 4 \quad \text{so} \quad f(1) = 2(1) - 4 = 2 - 4 = -2 \][/tex]
[tex]\[ g(x) = x - 3 \quad \text{so} \quad g(1) = 1 - 3 = -2 \][/tex]
Therefore,
[tex]\[ (f - g)(1) = f(1) - g(1) = -2 - (-2) \][/tex]
Simplify the expression by subtracting a negative value:
[tex]\[ = -2 + 2 = 0 \][/tex]

So, the final results are:
[tex]\[ \begin{array}{c} (f \cdot g)(x)=2x^2 - 10x + 12 \\ (f+g)(x)=3x - 7 \\ (f-g)(1)=0 \end{array} \][/tex]