Printing out pi as a symbol instead of the numerical value but calculating with the numerical value in the background in JavaScript

I am coding a calculator and I want that the calculator is displaying pi as a symbol and not as the numerical value.

My associated function is

function Pi(pi) {

document.getElementById(‘resultArea’).innerHTML += pi
eval(document.getElementById(‘resultArea’).innerHTML) = x
x = 3.1415926

}

And the associated HTML part is:

<td onclick=”Pi(‘π ‘)” class=”changing-button”>π</td>

InnerHTML is a div container or the part where the results are displayed respectively.