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Linearization Calculator – Find Linear Approximation

Find the linear approximation of a function at a point.

Calculate Linearization

How to Use

  1. Enter your function using standard notation (e.g., x^2, sin(x), exp(x))
  2. Specify the variable name (default is x)
  3. Enter the point where you want to linearize the function
  4. Click calculate to get the linear approximation

What is Linearization?

Linearization is the process of approximating a function near a point using its tangent line. The linear approximation L(x) at point a is given by: L(x) = f(a) + f'(a)(x - a), where f(a) is the function value and f'(a) is the derivative at point a.

This approximation works best for values of x close to a. The further x is from a, the less accurate the approximation becomes.

The Linearization Formula

  • L(x) = f(a) + f'(a)(x - a)
  • f(a) is the y-coordinate of the point on the curve
  • f'(a) is the slope of the tangent line
  • (x - a) represents the horizontal distance from the point

Applications of Linearization

  • Approximating complex functions with simpler linear ones
  • Error estimation in measurements
  • Physics: small angle approximations (sin(θ) ≈ θ)
  • Engineering: analyzing systems near equilibrium points
  • Economics: marginal analysis

Frequently Asked Questions

When is linearization most accurate?
Linearization is most accurate when x is very close to the point a. The approximation error grows as you move further from a, especially for functions with high curvature.
What's the difference between linearization and Taylor series?
Linearization is the first-order Taylor polynomial—it uses only the function value and first derivative. Taylor series can include higher-order terms for better accuracy over larger intervals.
Can I linearize any function?
You can linearize any function that is differentiable at the point of interest. If the function has a discontinuity or corner at that point, linearization isn't possible there.