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Desmos Tangent Line Calculator

Tangent Line Equation:

\[ y = f'(a) \times (x - a) + f(a) \]

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1. What is the Tangent Line Equation?

The tangent line equation represents the linear approximation of a function at a specific point. It's given by the formula: y = f'(a) × (x - a) + f(a), where f'(a) is the derivative at point a, and f(a) is the function value at point a.

2. How Does the Calculator Work?

The calculator uses the tangent line equation:

\[ y = f'(a) \times (x - a) + f(a) \]

Where:

Explanation: The tangent line represents the instantaneous rate of change of the function at the specified point, providing a linear approximation of the function's behavior near that point.

3. Importance of Tangent Lines

Details: Tangent lines are fundamental in calculus for understanding derivatives, optimization problems, curve sketching, and approximating non-linear functions with linear models.

4. Using the Calculator

Tips: Enter the mathematical function (e.g., x^2, sin(x), ln(x)) and the point of tangency. The calculator will compute the derivative and provide the tangent line equation.

5. Frequently Asked Questions (FAQ)

Q1: What types of functions can I input?
A: The calculator supports polynomial, trigonometric, exponential, and logarithmic functions (e.g., x^2, sin(x), exp(x), ln(x)).

Q2: How accurate is the tangent line approximation?
A: The approximation is most accurate very close to the point of tangency. Accuracy decreases as you move further from the point.

Q3: Can I use this for multivariable functions?
A: This calculator is designed for single-variable functions. Multivariable functions require tangent planes.

Q4: What if the derivative doesn't exist at my point?
A: The calculator will indicate if the derivative is undefined at the specified point (e.g., sharp corners, discontinuities).

Q5: How is the derivative calculated?
A: The calculator uses symbolic differentiation to compute the exact derivative of your input function.

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