Transcript text: If $f(x)=6 x^{2}-7 x-40$, find $f^{\prime}(x)$.
Solution
Solution Steps
Step 1: Identify the function
The given function is \( f(x) = 6x^{2} - 7x - 40 \).
Step 2: Apply the power rule
To find the derivative \( f^{\prime}(x) \), apply the power rule to each term. The power rule states that if \( f(x) = ax^{n} \), then \( f^{\prime}(x) = n \cdot a \cdot x^{n-1} \).
Step 3: Differentiate each term
For the term \( 6x^{2} \):
\[
\frac{d}{dx}(6x^{2}) = 2 \cdot 6 \cdot x^{2-1} = 12x
\]
For the term \( -7x \):
\[
\frac{d}{dx}(-7x) = 1 \cdot (-7) \cdot x^{1-1} = -7
\]
For the constant term \( -40 \):
\[
\frac{d}{dx}(-40) = 0
\]
Step 4: Combine the derivatives
Combine the derivatives of each term to find \( f^{\prime}(x) \):
\[
f^{\prime}(x) = 12x - 7
\]