Interpolation
We can say, interpolation is a technique of finding the value of a function inside the given range of arguments. Suppose, we have the values of y =f (x) for set of values of x. We have the data, x (argument): x1, x1, x2…xn and the corresponding values y: y0, y1, y2,…..yn. Then, we can say the process of finding the value of y corresponding to any value of x between x0 to xn is interpolation. Now, we can discuss about linear interpolation. The term “linear” means the degree of the equation is one. So, linear interpolation is a technique with linear function. If we have the two known points (x0, y0) and (x1, y1), the linear interpolation is the straight line between these points. That is (y – y0) over (x – x0) = (y1 – y0) over (x1 – x0). Now, we can discuss about polynomial interpolation, polynomials approximate continuous functions up to any required accuracy. Polynomials have exact evaluation and smooth and know the all derivatives are exactly.
Examples:
1. Using the linear interpolation formula, find the equation for the points (6, 8) and (10, 16).
2. Using the linear interpolation formula, for the coordinates of (1, 2) and (4, 5). Find the value of y when x = 2.