Pseudocode that gets 2 numbers from user and prints them in order until the user enters the first value of the trio as negative.

i=0

while (i>=0) {
read i,j
print i,j
}

Not sure whether "in order" means in the order given, or smallest first. If you need to sort them, I'm sure you can fill in the missing step.

You also say you want 2 numbers, then talk about the "trio." ???

With computers, you gotta say what you mean. Doesn't hurt much with people, either... Just sayin'

To write pseudocode for getting two numbers from the user and printing them in order until the user enters the first value of the trio as negative, you can follow these steps:

1. Read the first number from the user and store it in a variable called "num1".
2. Read the second number from the user and store it in a variable called "num2".
3. Create a loop that continues until "num1" becomes negative. Inside this loop, perform the following steps:
a. Print the value of "num1" to the console.
b. Swap the values of "num1" and "num2" to set "num2" as the new "num1" and update "num2" with a new input from the user.
4. End the loop.
5. Print a message to indicate that the loop has ended.

Here's the pseudocode representation of the above steps:

```
Read num1 from the user
Read num2 from the user

while num1 >= 0 do:
Print num1
temp = num1
num1 = num2
num2 = Read new number from the user

Print "Loop ended"
```

Please note that since pseudocode is not a specific programming language, the syntax may vary depending on the style or conventions being followed.