if statement ignoring inequality – Blancer.com Tutorials and projects

first time posting here so sorry if this isn’t as clear or efficient as can be, but I’m trying to write a program to take user inputs for 3 sides of a triangle and see if they are a valid triangle based on these rules:

a + b > c

a + c > b

b + c > a

So far, I’m just trying to prove a + b > c (which I called condition1). But in trying to solve this, it seems that the if statement I have is ignoring the a + b part and just checking a > c. Can anyone tell me what I’m doing wrong?

function isTriangle() {
  var input1 = document.getElementById("a");   // fetch the 3 numbers
  var input2 = document.getElementById("b");
  var input3 = document.getElementById("c");
  var displayAnswer = document.getElementById("display");

  function condition1(){
    if ((input1.value + input2.value) > input3.value)
    {
      return true;
    }
    else
    {
      return false;
    }
  }

  //our goal here is to use triangle inequality theorem
if (condition1(true)) {
  displayAnswer.innerHTML = "These three sides can form a   right triangle!";
}
else {
  displayAnswer.innerHTML = "These three sides cannot form a   right triangle!";
}

  
}

<!DOCTYPE html>
<html>
<head>
    <title>Project 3</title>
    <script src="proj3.js" type="text/javascript"></script>
</head>
  
<body>
<h1>Triangle Tester</h1>

  <p> Please input the length (integer) of the first side of the triangle: </p>
  <input id="a" type="text" size="3" /> 

  <p> Please input the length (integer) of the second side of the triangle: </p>
  <input id="b" type="text" size="3" /> 

  <p> Please input the length (integer) of the third side of the triangle: </p>
  <input id="c" type="text" size="3" /> 
  
  <br />
  <br />
  <span id="display"></span>

  <br />

  <button onclick="isTriangle();">(2)</button>
 
</body>
</html>