How to Show Decimal on Calculator for Square Root

When calculating square roots, you often need to display the result with decimal places. This guide explains how to properly show decimals in square root calculations across different calculator types and provides a practical tool to help you.

How to Display Decimals in Square Root Calculations

Displaying decimals in square root calculations depends on the type of calculator you're using. Here are the most common methods:

Scientific Calculators

Scientific calculators typically have a dedicated square root function. To display decimals:

Enter the number you want to find the square root of
Press the square root button (often labeled √)
If you need decimal places, press the decimal point button and then the number of decimal places you want
Press the equals button to see the result

Graphing Calculators

Graphing calculators offer more advanced options for displaying square roots with decimals:

Enter the number in the home screen
Press the 2nd function key and then the square root button
Use the arrow keys to move the cursor to the decimal point
Press the enter key to confirm the number of decimal places

Programmable Calculators

For programmable calculators, you can create custom programs to display square roots with specific decimal places:

Create a new program
Use the square root function
Add code to format the output to your desired decimal places
Run the program with your input number

Online Calculators

Most online calculators allow you to specify the number of decimal places in the result:

Enter the number in the input field
Look for a decimal places setting (often a dropdown or input field)
Select or enter the number of decimal places you want
Click calculate to see the result

Note: The number of decimal places you choose should match the precision needed for your specific calculation. More decimal places provide greater accuracy but may not be necessary for all applications.

Different Calculator Methods for Square Roots

Calculators use various methods to compute square roots, each with its own approach to displaying decimal places:

Direct Calculation

Most calculators use direct computation methods that can display square roots with any number of decimal places you specify.

Iterative Methods

Some advanced calculators use iterative methods like Newton's method to approximate square roots. These methods can be configured to show results with specific decimal precision.

Lookup Tables

Programmable calculators might use lookup tables for common square roots, but you can still specify decimal places in the output formatting.

Algorithmic Methods

Modern calculators often use algorithmic methods that can be adjusted to display square roots with the exact number of decimal places you need.

√x = y where y² ≈ x
For decimal display: y = round(√x, n) where n is the number of decimal places

Common Mistakes When Showing Decimals

Avoid these common errors when displaying decimal places in square root calculations:

Rounding Too Early

Don't round the intermediate steps in your calculation. Always keep more decimal places during computation and round only at the final step.

Incorrect Decimal Places

Choose the appropriate number of decimal places based on the precision needed for your specific application.

Not Specifying Decimal Places

Always specify the number of decimal places you want, even if you think the default is sufficient.

Using Inconsistent Methods

Be consistent with your method for displaying decimal places across all calculations.

Tip: For most practical applications, 2-4 decimal places are sufficient. For scientific or engineering work, you may need more precision.

Practical Examples of Decimal Square Roots

Here are some examples of square roots displayed with different decimal places:

Number	√ (2 decimal places)	√ (4 decimal places)	√ (6 decimal places)
2	1.41	1.4142	1.414213
5	2.24	2.2361	2.236068
10	3.16	3.1623	3.162278
15	3.87	3.8729	3.872983
20	4.47	4.4721	4.472136

These examples show how the same square root can be displayed with different levels of precision depending on your needs.

Frequently Asked Questions

How many decimal places should I use for square roots?: The number of decimal places depends on your specific application. For most practical purposes, 2-4 decimal places are sufficient. For scientific or engineering work, you may need more precision.
Can I round square roots to whole numbers?: Yes, you can round square roots to whole numbers if that's appropriate for your calculation. However, be aware that this may introduce significant rounding errors for some numbers.
Do all calculators show the same number of decimal places?: No, different calculators may show different default decimal places. Always check your calculator's settings or documentation to understand how it displays square roots.
Is it better to show more or fewer decimal places?: It depends on your needs. More decimal places provide greater precision but may not be necessary for all applications. Fewer decimal places are easier to read but may lack the precision needed for some calculations.
Can I change the number of decimal places after calculating the square root?: In most cases, you should specify the number of decimal places before performing the calculation. However, some advanced calculators allow you to reformat the result after it's been computed.