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Tangent Line Equation Calculator

Tangent Line Equation:

\[ y - y_0 = m (x - x_0) \]

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1. What is the Tangent Line Equation?

The tangent line equation represents the straight line that just touches a curve at a specific point, having the same slope as the curve at that point. It's a fundamental concept in calculus and geometry.

2. How Does the Calculator Work?

The calculator uses the point-slope form of a line equation:

\[ y - y_0 = m (x - x_0) \]

Where:

Explanation: The equation describes a line passing through point (x₀, y₀) with slope m.

3. Importance of Tangent Lines

Details: Tangent lines are crucial in calculus for understanding derivatives, approximating functions near specific points, and solving optimization problems.

4. Using the Calculator

Tips: Enter the coordinates of the point of tangency (x₀, y₀) and the slope (m) of the tangent line at that point. The calculator will provide both the point-slope form and slope-intercept form of the equation.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between tangent line and secant line?
A: A tangent line touches the curve at exactly one point, while a secant line intersects the curve at two or more points.

Q2: How is the slope (m) determined for a function?
A: For a function f(x), the slope at point x₀ is the derivative f'(x₀).

Q3: Can a tangent line intersect the curve at other points?
A: Yes, except at the point of tangency where it only touches the curve without crossing.

Q4: What if the slope is infinite?
A: This indicates a vertical tangent line, which has the equation x = x₀.

Q5: How is this used in real-world applications?
A: Tangent lines are used in physics for instantaneous velocity, in economics for marginal analysis, and in engineering for linear approximations.

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