title: Excel: Fill a range of cells with a value or formula depending on only one cell
body: <p>We have a project on a certain math subject and I am done with the computations and it works just fine. So the task is, let's say you have a system of linear equations of certain number of unknowns, you input the number of unknowns, and fill in the values, and using matrix computations, find all the value of unknowns.</p>
  
  <p>To make this short, I already finished the "find the value of unknowns" along with the computation, I checked it, and it seems fine. I can put 6 as the number of unknowns and it automatically computes the inverse of a 6x6 matrix and it will return the 6 unknown values using Index INDIVIDUALLY. </p>
  
  <p>(<strong><em>Note:</em></strong> <em>We aren't allowed to use VBA or Macros since we haven't discussed that yet.</em></p>
  
  <p>The problem is, I don't know how to automatically fill a <strong>RANGE</strong> of cells with a <strong>VALUE</strong> <strong><em>or</em></strong> <strong>A FORMULA</strong> based on a <strong>SINGLE</strong> cell value.</p>
  
  <p>For example, In cell A1, I will input 5 (which indicates the number of unknowns), then upon inputting this and hitting enter, let's say a range of cells A2 to A6 (which is 5 cells) will be automatically filled with incremented letters, like for A2 -> A ; A3 -> B ; ... A6 -> E, of which these letters indicate the 5 unknowns.</p>
  
  <p><strong>PROBLEM 2.</strong>
  Another follow up question, let's say I input again 5, which again stands for the number of missing values/unknowns, in A1, besides the column of the variables A,B,C,D,E (5 unknowns), I want to automatically fill column B respectively with values from an array.</p>
  
  <p>This is just the same with my first problem but this time, instead of incremented letters, it would be Incremented Index function.</p>
  
  <p>For example: I input 5</p>
  
  <p><strong>*Column A</strong> will automatically be filled with the variables/letters</p>
  
  <p><strong>*Column B</strong> will automatically be filled with the values from an array that's computed using a formula but is not shown independently on cells. 
  I already have the formula </p>
  
  <p>INDEX(Formula I created, Row number of the answer from the Formula I created , Column number of the answer from the formula I created)</p>
  
  <p>The answers from the formula I made myself is also an array, an "n" rows and 1 column array. If I put the Index formula on a SINGLE cell, it returns specified row number value from the array that resulted in the computation from my formula
  What I want is for example, for 5 unknowns</p>
  
  <pre><code>   **A      |       B**
  </code></pre>
  
  <p>1|.......5..........................             </p>
  
  <p>2|.......A..............Some Value 1 </p>
  
  <p>3|.......B..............Some Value 2</p>
  
  <p>4|.......C..............Some Value 3</p>
  
  <p>5|.......D..............Some Value 4</p>
  
  <p>6|.......E..............Some Value 5</p>
  
  <p>Wherein the "Some Value" is the Arrayed Answer from my formula and the "1,2,3,4,5" specifies the row number from that arrayed answer.
  This is upon inputting the matrix values, inputting the  number of unknowns "n" in A1, and automatically filling a range of cells A2 to A"n" with letters A up to what letter "n" corresponds, and automatically filling a range of Cells B2 to B"n" with my formula but with incremented row number for every row in the Index(Formula, <strong>Row number</strong> , Column number) function.</p>
  
  <p>Note: I hope there's a way to do this using excel functions only since we haven't discussed VBA or Macros yet so we can't use those, and even If we can, I have no knowledge for that. haha. :D</p>
  
  <p>THANK YOU THANK YOU THANK YOU SO MUCH IN ADVANCED! Cheers. :D</p>