Algrebraic Functions

  • Thread starter Thread starter Jpleasant
  • Start date Start date
J

Jpleasant

How would you solve a function with input 1 output 8.

Then input 2 output 14.

next input 3 output is blank

then input is blank Output is 24.

the input is blank and the out put is 28.

Finally, the input is 6 and the output is blank.
 
It occurred to me that if you assume the input blanks are 4 and 5, then you
could use the Add Trendline option within Excel charts to show you what the
potential functions could be.

Try plotting x: 1, 2, (blank cell), 4, 5 against y: 8, 14, (blank cell), 24,
28

Use an x-y scatter chart and, when plotted, right click on a data point and
select Add Trendline. On the Type tab, I'd try selecting Polynomial (order at
least 2). On the Options tab click Display equation on chart.

Hopefully you will have some idea from the maths related work you're doing
which type of function you should be looking for (polynomial, exponential,
power etc) and if polynomial then the order of polynomial you are typically
working with (quadratic, cubic etc).

Regards,

Tom
 
First the bad I don't think you can use Excel to just give you the
function you require (by typing in the inputs and outputs).

The good you could use Excel to test a function you come up with
yourself.

It seems reasonable that the Input 'blanks' in your data are 4 and 5. This
gives a series of input/ouput pairs as (1,8) (2,14) (3,?) (4,24) (5,28)
(6,?). So if you type the numbers 1 to 6 in say cells A1 to A6, then you can
try different 'functions' in cells B1 to B6, such as using a formula in B1
like =(A1*2) + 6

Then drag fill this formula down to B6, so that B2 holds formula =(A2*2) +
6, B3 holds formula =(A3*2) + 6 etc.

This formula would translate to a function: output = (input x 2) + 6

This isn't the function you're looking for by the way, but you should be
able to find the one you need with some maths playing about!

Regards,

Tom
 
Back
Top