Example: Exact Polynomials With Known Data Points
When you need to describe a set of points in terms of a function, you can use the Exact Polynomials program to determine a polynomial approximation.
Example
Find a polynomial that fits the given numbers and interpolate for x = 3.1.|
|
|
x |
y |
|
|
|
| 0 | 6 |
| 1 | 7 |
| 2 | 14 |
| 3 | 33 |
| 4 | 70 |
|
|
|
Procedure |
Press |
Display |
|---|---|---|
|
|
||
| Select the program | [ RUN ] { MTH } { INT } { PLY } { NEW } |
 |
| Enter the number of points | 5 { n } { EOD } |
 |
| Enter the points | 0 [ x~t ] 6 { ENT } |
 |
| 1 [ x~t ] 7 { ENT } |
 |
|
| 2 [ x~t ] 14 { ENT } |
 |
|
| 3 [ x~t ] 33 { ENT } |
 |
|
| 4 [ x~t ] 70 { ENT } |
 |
|
| Proceed with program | { EOD } |  |
| View the coefficients | { YES } |  |
| { NXT } |  |
|
| { NXT } |  |
|
| { NXT } |  |
|
| { NXT } |  |
|
| Proceed with program | { NO } |  |
| Interpolate at 3.1 | { YES } 3.1 { x } |
 |
The polynomial is : y = 6 + 0x + 0x2 + 1x3, which can be written as: y = 6 + x3.
☚ Back