Diamond Math Symbol Question... Let's see if WTM posters know more than google. :)

[Michelle My Bell]

This is Michelle's daughter... a few weeks ago, I posted a math question on here, and now I have another one. lol

 

Ok, so here is the math problem:

 

Let a ♦ b = (a-b)³ for all integers a and b. Which if the following is the value of 3 ♦ (-2) ?

 

My question is:

 

What in the world are those diamond symbols?? And how do you use them?? (Ok, so that was two questions....) I have googled and googled an googled, and have found no answers. Although I usually just assume if it's not on google it doesn't exist, I thought I'd try one more stop before throwing my math book at the wall in frustration.

 

Thank you. :001_smile:

[TheReader]

I have no idea.

 

But since the problem gives what a (diamond) b equals, you can just use that equation instead.

 

So, in this case, (3 - -2)^3, which then is (3+2)^3, so (5)^3, so 5 x 5 x 5, so 125.

 

Never seen the diamond, but having the sub equation makes it rather irrelevant, I think.

[Rivka]

I have no idea.

 

But since the problem gives what a (diamond) b equals, you can just use that equation instead.

 

Right. The function "diamond" is defined in the problem. "Diamond" doesn't mean something stable across all math problems, it's specific to this one. They could have used "heart" or "pentagon" or "sporfle" or anything else. Solve it like TheReader solved it.

[chepyl]

The first part of the problem defines what the function of the diamond is. Now you solve using that function: (3-(-2))cubed. (I am on my phone and cannot do an exponent ;)