Questions: Find the derivative of the following function.
y=-5 x^2+7 cos x
dy/dx=
Transcript text: Find the derivative of the following function.
\[
\begin{array}{l}
y=-5 x^{2}+7 \cos x \\
\frac{d y}{d x}=\square
\end{array}
\]
$\square$
Solution
Solution Steps
To find the derivative of the given function, we need to apply the rules of differentiation. Specifically, we will use the power rule for the term involving \(x^2\) and the derivative of the cosine function for the term involving \(\cos x\).
Step 1: Define the Function
We start with the function given in the problem:
\[
y = -5x^2 + 7\cos(x)
\]
Step 2: Differentiate the Function
To find the derivative \(\frac{dy}{dx}\), we apply the power rule and the derivative of the cosine function:
\[
\frac{dy}{dx} = \frac{d}{dx}(-5x^2) + \frac{d}{dx}(7\cos(x))
\]
Calculating each term, we have:
\[
\frac{d}{dx}(-5x^2) = -10x
\]
\[
\frac{d}{dx}(7\cos(x)) = -7\sin(x)
\]
Thus, combining these results, we get:
\[
\frac{dy}{dx} = -10x - 7\sin(x)
\]
Final Answer
The derivative of the function is:
\[
\boxed{\frac{dy}{dx} = -10x - 7\sin(x)}
\]