If [tex]f(x) = 2x^4 - 3e^x[/tex], find:

[tex]\[
\begin{array}{l}
f^{\prime}(x) = \square \\
f^{\prime}(1) = \square \\
f^{\prime \prime}(x) = \square \\
f^{\prime \prime}(1) = \square
\end{array}
\][/tex]



Answer :

Let's find the derivatives and evaluations step by step for the function [tex]\( f(x) = 2x^4 - 3e^x \)[/tex].

1. First Derivative [tex]\( f'(x) \)[/tex]

To find the first derivative of [tex]\( f(x) \)[/tex], we need to differentiate each term individually:

[tex]\[ f(x) = 2x^4 - 3e^x \][/tex]

The derivative of [tex]\( 2x^4 \)[/tex] is [tex]\( 8x^3 \)[/tex] and the derivative of [tex]\( -3e^x \)[/tex] is [tex]\( -3e^x \)[/tex]. Thus, the first derivative is:

[tex]\[ f'(x) = 8x^3 - 3e^x \][/tex]

2. Evaluation of the First Derivative at [tex]\( x = 1 \)[/tex]

Next, we substitute [tex]\( x = 1 \)[/tex] into the first derivative to find [tex]\( f'(1) \)[/tex]:

[tex]\[ f'(1) = 8(1)^3 - 3e^{1} \][/tex]

Since [tex]\( 1^3 \)[/tex] is [tex]\( 1 \)[/tex] and [tex]\( e^1 \)[/tex] is [tex]\( e \)[/tex], we get:

[tex]\[ f'(1) = 8 - 3e \][/tex]

3. Second Derivative [tex]\( f''(x) \)[/tex]

To find the second derivative, we differentiate the first derivative [tex]\( f'(x) = 8x^3 - 3e^x \)[/tex]:

The derivative of [tex]\( 8x^3 \)[/tex] is [tex]\( 24x^2 \)[/tex] and the derivative of [tex]\( -3e^x \)[/tex] remains [tex]\( -3e^x \)[/tex]. Thus, the second derivative is:

[tex]\[ f''(x) = 24x^2 - 3e^x \][/tex]

4. Evaluation of the Second Derivative at [tex]\( x = 1 \)[/tex]

Finally, we substitute [tex]\( x = 1 \)[/tex] into the second derivative to find [tex]\( f''(1) \)[/tex]:

[tex]\[ f''(1) = 24(1)^2 - 3e^{1} \][/tex]

Since [tex]\( 1^2 \)[/tex] is [tex]\( 1 \)[/tex] and [tex]\( e^1 \)[/tex] is [tex]\( e \)[/tex], we get:

[tex]\[ f''(1) = 24 - 3e \][/tex]

Therefore, the answers are:

[tex]\[ \begin{array}{l} f^{\prime}(x) = 8x^3 - 3e^x \\ f^{\prime}(1) = 8 - 3e \\ f^{\prime \prime}(x) = 24x^2 - 3e^x \\ f^{\prime \prime}(1) = 24 - 3e \end{array} \][/tex]