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The values of a function f(x) are tabulated below:
Using Newton's forward difference formula, the cubic polynomial that can be fitted to the above data, is
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- 2x3 + 7x2 – 6x + 2
- 2x3 - 7x2 + 6x – 2
- x3 – 7x2 – 6x2 + 1
- 2x3 - 7x2 + 6x + 1
Correct Option: D
Difference table as
We take x0 = 0, p = | = x [∵ k = 1] | k |
using Newton’s forward interpolation formulae, we get
f(x) = f(0) + | Δ f(0) + | 1 | 1.2 |
∆²f(0) + | ∆3f(0) | 1.2.3 |
= 1 + x(1) + | (-2) + | (12) | 2 | 6 |
= 1 + x + (x – x²) + 2x(x² – 3x + 2)
= 1 + x + x – x² + 2x3 – 6x + 4x
= 2x3 – 7x² + 6x + 1