Connect with experts and get insightful answers on IDNLearn.com. Our experts provide timely and precise responses to help you understand and solve any issue you face.

Suppose \( f(x) \) and \( f^{\prime}(x) \) have the values shown.

\begin{tabular}{|c|r|r|r|r|r|}
\hline
[tex]$x$[/tex] & 44 & 45 & 46 & 47 & 48 \\
\hline
[tex]$f(x)$[/tex] & -6 & 8 & -2 & 1 & -3 \\
\hline
[tex]$f^{\prime}(x)$[/tex] & -5 & 8 & 4 & 1 & -10 \\
\hline
\end{tabular}

Let \( g(x) = f\left(5 x^2 - 4 x - 61\right) \).

Find \( g^{\prime}(5) \).

[tex]\( g^{\prime}(5) = \square \)[/tex]


Sagot :

To find the value of \( g'(5) \), we start by understanding the function \( g(x) \) and then compute its derivative.

Given:
[tex]\[ g(x) = f(5x^2 - 4x - 61) \][/tex]

To find \( g'(x) \), we need to apply the chain rule. The chain rule for derivatives tells us:
[tex]\[ g'(x) = f'(u) \cdot \frac{du}{dx} \][/tex]
where \( u = 5x^2 - 4x - 61 \).

First, let's differentiate \( u \) with respect to \( x \):
[tex]\[ u = 5x^2 - 4x - 61 \][/tex]
[tex]\[ \frac{du}{dx} = 10x - 4 \][/tex]

Next, we plug this into the chain rule formula:
[tex]\[ g'(x) = f'(5x^2 - 4x - 61) \cdot (10x - 4) \][/tex]

We now need to evaluate this expression at \( x = 5 \):
[tex]\[ g'(5) = f'(5(5^2) - 4(5) - 61) \cdot (10(5) - 4) \][/tex]

First, compute the argument of \( f' \) (i.e., the inner function):
[tex]\[ 5(5^2) - 4(5) - 61 = 5(25) - 20 - 61 = 125 - 20 - 61 = 44 \][/tex]

We now look up \( f'(44) \) in the given table:
[tex]\[ f'(44) = -5 \][/tex]

Using this value in our derivative expression:
[tex]\[ g'(5) = f'(44) \cdot (10(5) - 4) = -5 \cdot (50 - 4) = -5 \cdot 46 = -230 \][/tex]

Therefore:
[tex]\[ g'(5) = -230 \][/tex]