this paper, solving the equations lgx + x2 = 0, for example, details how to use Excel 2007 as a calculation tool to solve this equation.

We just need to first cell in A1 enter a random number, such as "1", and then the cell B1 enter the formula in accordance with the equation solving "= LOG (A1) + A1 ^ 2". Now click on the function area "Data" tab "Data Tools" function group "what if analysis" button in the pop-up menu click on "Single Variable" command, open the "Single Variable" dialog box. Shown in Figure 1, the "target cell" input box, enter the cell where the formula "$ B $ 1", in the middle of the "target" input box, enter "0" in the bottom of the "variable unit grid "input box, enter" $ A $ 1 ". Confirmed, you can get a dialog box shown in Figure 2. Close this dialog box, in the A1 cell can seek to the desired solution of the equation.

Figure 1

Figure 2

See it now? Figure 1, the target cells that contain formulas that cell, while the target is that it is the equation of the right value, so if we require solutions of equations lgx + x2 = 3, then this value is "3", while the variable unit lattice is shown that the results of the cell, which is the formula where the variable cell.

If you calculate the results were not accurate, we can click on the Excel upper left corner of the "Office button" in the pop-up menu in the lower right corner of the "Excel Options" button, open the "Excel Options" dialog. Then the list on the left click on the "formula" the right to select the "Enable iterative calculation" restore option, and below it the "maximum error" input box, enter "0", shown in Figure 3. This can be a more accurate result.

Figure 3