>thinking about math at 3am Can someone explain to me how

>>35301959

think about it this way, 1 can also be written as 1/1, or 2/2, or any number where the denominator and numerator are the same.

2 can be considered 2/1, or 4/2. following this 1.5 can be written as 3/2, and to swap them over, though im not sure the practical application of doing so, can be written as 2/3, aka .6, or close enough that most people write it that way.

>>35302050
It looks fine while using fractions, but fucks up as soon as you use normal numbers. The whole reason this shit is on my mind is because I understand 2/3=.6 and 3/2=1.5

>>35301959
All about them definitions of inverse my man. I think thats where ur encountering the trouble

>>35302110
>definitions of inverse
Inverse as in opposite.

>>35301959
This is better referred to as the "reciprocal" of a number. It's 1/that number, or flipping the fraction upside down. 1.5 = 3/2, flip it around and you get 2/3. 1/1.5 = 2/3
When you multiply a number by its reciprocal, you always get 1. We call this the "multiplicative inverse". -2 is the "additive inverse" of 2. Additive inverse is "what number added to this number equals zero." Noting that subtraction is a special case of addition.

ban math threads.

File: THanks.jpg (56KB, 405x348px) Image search: [Google]

56KB, 405x348px

>>35302155
Thank you. This is more or less what I was confused about. I didn't really think of it in terms of the fraction being a division equation in itself, so the opposite would obviously be multiplication, not addition like I was thinking.

>>35301959
1.5^-1 = 1/1.5
=1/(3/2)
=0.6666

>>35301959
>I would think the inverse of a number would be what makes it equal 1.

It does... if you multiply them, not add them.

(4/9)*(9/4)=1

Why should 0.444... + 2.25 = 1?

/thread I guess

>>35302215
Yep, that's where I fucked up, like I said here >>35302190

>>35302190
Also if it were defined as the number added to that number to get 1... that wouldn't be a very useful concept. -2 would be the additive inverse of 3 and so on, which would be weird. It's a coherent concept, but the definition of additive inverse we use is more logical, and yields more applications.

>>35301959
Can you rephrase your question? I don't get exactly what doesn't make sense.

Whatever the case, if you graph a function that equals 1/x, you can see the inverse for every x-number.
http://www.wolframalpha.com/input/?t=crmtb01&f=ob&i=f(x)+%3D+1%2Fx

>>35301959

>Can someone explain to me how the hell the inverse of 1.5 is 0.6666?

1.5 = 1.5/1
1/1.5 = 0.6666

1/1.5 * 1.5/1 = 1