Expression Node

[SercoSteveB]

Which of the following contain valid Expression Node syntax?

[crossrulz]

Well I learned something today.  The answer is apparently A,B, and C.

I knew for sure A.  And I knew definately not D.  So can any letter be a variable then?

[SercoSteveB]

HI GM, you win the prize for fastest reply ever. Not sure about what letters are valid.  What do you think about the '+4' one?

[crossrulz]

I actually would have replied sooner except I had to reboot my computer.

The '+4' makes sense to me.  I will have to use that one more.  It takes up less space than the 'x+4' that I'm used to using.

[SercoSteveB]

The '+4' gives me a value of 4 on the output, irrespective of the input value. 

Do you see something different?

w.r.t. which letters; I tried upper and lower case letters from the start and the end of the alphabet, seems we can use anything.

[crossrulz]

Actually, I now remember running into that trap about a year or so ago.  '+4' is a number and therefore a constant.  It's just a number with a sign, just like putting in '-4'.

[Pratibha]

Ans:-A , B and C.

[Asha_Nagaraj]

Ans is A , B and C.

[faymia]

The equal sign is not valid expression node syntax... So, the answers are A, B, and C.

[RAMESHB]

Ans is A,B and C.

[machinevision]

ans:c