What would be the difference here in using || and && … why my code works but doesnt pass the test

cheers

**Your code so far**

```
// Setup
function abTest(a, b) {
// Only change code below this line
if (a && b < 0) {
return;
}
// Only change code above this line
return Math.round(Math.pow(Math.sqrt(a) + Math.sqrt(b), 2));
}
// Change values below to test your code
abTest(2,2);
```

**Your browser information:**

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**Link to the challenge:**