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jxaxbx
Jul 15, 2008, 04:28 PM
Hello,

Here is my table:

x
1
2
3
missing value
missing value
6

y corresponds with the appropriately (I just can't make the table in this format)
8
14
missing value
24
28
missing value
Can anyone help me find the rule so that I can figure out the missing values?

Thank you!

ebaines
Jul 16, 2008, 06:05 AM
If you assume that the missing values for the x variable are 4 and 5 (which looks reasonable), then you can fit a quadratic to the values

x1,y1 = 1,8
x2,y2 = 2, 14
x4,y4 = 4, 24.

So you end up with 3 equations in 3 unknowns based on y = Ax^2 + Bx +C.

Like this:

A(1^2) + B*1 + C = 8
A(2^2) + B*2 + C = 14
A(4^2) + B*4 +C = 24

Solve for A, B, and C, and check with the other value you are given: f(5) = 28, to double check that this works. You can then find the missing values for y for x = 5 and x=6. Hope this helps.