The functions [tex][tex]$f$[/tex][/tex] and [tex][tex]$g$[/tex][/tex] are defined as follows:

[tex]\[ f(x) = -5x - 1 \][/tex]
[tex]\[ g(x) = -2x^3 - 5 \][/tex]

Find [tex][tex]$f(4)$[/tex][/tex] and [tex][tex]$g(-4)$[/tex][/tex]. Simplify your answers as much as possible.

[tex]\[ f(4) = \][/tex]
[tex][tex]$\square$[/tex][/tex]

[tex]\[ g(-4) = \][/tex]
[tex][tex]$\square$[/tex][/tex]



Answer :

To determine the values of [tex]\( f(4) \)[/tex] and [tex]\( g(-4) \)[/tex] using the given functions [tex]\( f \)[/tex] and [tex]\( g \)[/tex], let's take it step by step.

First, we use the function [tex]\( f(x) = -5x - 1 \)[/tex] to find [tex]\( f(4) \)[/tex].

1. Substitute [tex]\( x = 4 \)[/tex] into the function [tex]\( f \)[/tex]:
[tex]\[ f(4) = -5(4) - 1 \][/tex]

2. Calculate the value inside the parentheses:
[tex]\[ -5(4) = -20 \][/tex]

3. Subtract 1 from -20:
[tex]\[ -20 - 1 = -21 \][/tex]

So,
[tex]\[ f(4) = -21 \][/tex]

Next, we use the function [tex]\( g(x) = -2x^3 - 5 \)[/tex] to find [tex]\( g(-4) \)[/tex].

1. Substitute [tex]\( x = -4 \)[/tex] into the function [tex]\( g \)[/tex]:
[tex]\[ g(-4) = -2(-4)^3 - 5 \][/tex]

2. First, calculate [tex]\( (-4)^3 \)[/tex]:
[tex]\[ (-4)^3 = -64 \][/tex]

3. Then multiply by -2:
[tex]\[ -2(-64) = 128 \][/tex]

4. Finally, subtract 5 from 128:
[tex]\[ 128 - 5 = 123 \][/tex]

So,
[tex]\[ g(-4) = 123 \][/tex]

To summarize:

[tex]\[ f(4) = -21 \][/tex]
[tex]\[ g(-4) = 123 \][/tex]