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Find the slope of the tangent line of cos(3x) at x=2.

User Anerdw
by
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1 Answer

1 vote

Main Answer:

The slope of the tangent line to the function
\(y = \cos(3x)\) at \(x = 2\) can be found by taking the derivative of the function with respect to
\(x\) and then evaluating it at
\(x = 2\).

Step-by-step explanation:

1. **Find the Derivative:**

Start by finding the derivative of the given function
\(y = \cos(3x)\) with respect to
\(x\). Use the chain rule since there is a composition of functions. The derivative of
\(\cos(u)\) with respect to
\(u\) is \(-\sin(u)\), and then multiply by the derivative of the inner function.


\[ (dy)/(dx) = -\sin(3x) \cdot (d(3x))/(dx) \]


\[ (dy)/(dx) = -3\sin(3x) \]

2. **Evaluate at
\(x = 2\):**

Substitute
\(x = 2\) into the derivative to find the slope at that specific point.


\[ \text{Slope at } x = 2: \quad m = -3\sin(6) \]

3. **Calculate the Numerical Value:**

Use a calculator to find the numerical value of
\(-3\sin(6)\).

So, the slope of the tangent line to
\(y = \cos(3x)\) at \(x = 2\) is \(-3\sin(6)\). You can use a calculator to get the approximate numerical value if needed.

User Amitai Fensterheim
by
8.8k points