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    Goodnight :wavey:
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    (Original post by AngryJellyfish)
    Goodnight :wavey:
    Night night!
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    (Original post by Matrix123)
    Soooo...the value of y has the opposite sign of the value of x? I'm sure that's not technically correct I'll wait to see what Associativity has to say on the matter

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    Generally, those double bars would be spoken to be the "modulus" or "mod" of the number (not to be confused with the modulo function, which is something different). So for instance, |x| would be read as "the modulus of x", or lazy (most) mathematicians would speak it to be "mod x". You might also hear this called the "absolute value", means the same.

    The definition you gave was right in this context, for real numbers. You can think about it as the "Magnitude" of the number; i.e how big it is, regardless of its sign. So yes, you can define it as follows

    {x, for x>=0
    |x|= {
    {-x. for x<0.

    so |-5| = 5. Notice that for x=5 and x=-5, the value of |x| is the same. You can think of this as being because they have the same magnitude, just different signs.
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    |x| has the shape of graph shown with both the person's hands going straight up, it's basically like drawing y=x, but reflecting everything left of the y axis in the x axis, to get a graph that looks like this: \/ (excuse ascii )

    The other ones on there you might not have met are cot x (which is 1/tanx), log_a (x) (which is a number such that a^(log_a (x)) = x), and possibly x^2+y^2=a^2 (which is a circle).
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    Sorry I can't rate you Matrix, the maths vid is great.

    Note, that the last one on your pic isn't actually a function, so they couldn't really include this and call it "Uptown Funktions" .

    If you like that, you may like (perhaps even find useful) this, and other videos by these people. They're a bit of a novelty, but actually really useful for explaining how sorting algorithms work. Here is the folk dance for the quicksort algorithm.

    You'll need an explanation on paper to understand how this works properly, but this is a nice demo.
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    (Original post by Associativity)
    Sorry I can't rate you Matrix, the maths vid is great.

    Note, that the last one on your pic isn't actually a function, so they couldn't really include this and call it "Uptown Funktions" .

    If you like that, you may like (perhaps even find useful) this, and other videos by these people. They're a bit of a novelty, but actually really useful for explaining how sorting algorithms work. Here is the folk dance for the quicksort algorithm.

    You'll need an explanation on paper to understand how this works properly, but this is a nice demo.
    I'm glad you're chief morale officer :proud:
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    (Original post by iEthan)
    I'm glad you're chief morale officer :proud:
    How come
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    (Original post by Associativity)
    How come
    You're good at boosting morale :bigsmile:
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    if u let me win I'll give you a cookie
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    (Original post by bluemadhatter)
    if u let me win I'll give you a cookie
    Deal.

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    (Original post by Associativity)
    Generally, those double bars would be spoken to be the "modulus" or "mod" of the number (not to be confused with the modulo function, which is something different). So for instance, |x| would be read as "the modulus of x", or lazy (most) mathematicians would speak it to be "mod x". You might also hear this called the "absolute value", means the same.

    The definition you gave was right in this context, for real numbers. You can think about it as the "Magnitude" of the number; i.e how big it is, regardless of its sign. So yes, you can define it as follows

    {x, for x>=0
    |x|= {
    {-x. for x<0.

    so |-5| = 5. Notice that for x=5 and x=-5, the value of |x| is the same. You can think of this as being because they have the same magnitude, just different signs.
    Ohhh OK.
    Oooh that's cool! :yep: thanks for clearing that up
    (Original post by Associativity)
    |x| has the shape of graph shown with both the person's hands going straight up, it's basically like drawing y=x, but reflecting everything left of the y axis in the x axis, to get a graph that looks like this: \/ (excuse ascii )

    The other ones on there you might not have met are cot x (which is 1/tanx), log_a (x) (which is a number such that a^(log_a (x)) = x), and possibly x^2+y^2=a^2 (which is a circle).
    Ahhh I understand I've come across the circle one before
    (Original post by Associativity)
    Sorry I can't rate you Matrix, the maths vid is great.

    Note, that the last one on your pic isn't actually a function, so they couldn't really include this and call it "Uptown Funktions" .

    If you like that, you may like (perhaps even find useful) this, and other videos by these people. They're a bit of a novelty, but actually really useful for explaining how sorting algorithms work. Here is the folk dance for the quicksort algorithm.

    You'll need an explanation on paper to understand how this works properly, but this is a nice demo.
    No worries. Haha I'm glad you liked it well, it was rather enjoyable until my teacher played it and tried to get us to do the moves

    Ahh that's absolutely unbelievable! Oh well, at least the others are right. Thanks for pointing that out

    Oooh I love the sound of this! I'll watch it at some point today:yep: I'm learning about quicksort algorithms so I'm sure this will really come in handy

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    \begin{equation*}R = 

 

\displaystyle{\sum_{i=1}^n (x_i-\bar{x})(y_i- 

 

\bar{y})}}{\displaystyle{\left[ 

 

\sum_{i=1}^n(x_i-\bar{x})^2 

 

\sum_{i=1}^n(y_i-\bar{y})^2\right]^{1/2}}} 

 

\end{equation*}

    :proud:
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    Did someone say cookie?:ahee:

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    (Original post by Associativity)
    Sorry I can't rate you Matrix, the maths vid is great.

    Note, that the last one on your pic isn't actually a function, so they couldn't really include this and call it "Uptown Funktions" .

    If you like that, you may like (perhaps even find useful) this, and other videos by these people. They're a bit of a novelty, but actually really useful for explaining how sorting algorithms work. Here is the folk dance for the quicksort algorithm.

    You'll need an explanation on paper to understand how this works properly, but this is a nice demo.
    Haha, this video is amazing! :yep: :top:
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    Morning :yawn:
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    (Original post by iEthan)
    Morning :yawn:
    Morning, Ethan!

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    (Original post by Matrix123)
    Morning, Ethan!

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    Hi Matrix!!! :jive:

    How're you? :hugs:
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    (Original post by iEthan)
    Hi Matrix!!! :jive:

    How're you? :hugs:
    I'm great thanks! :hugs:

    How are you!? :jive:
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    (Original post by Matrix123)
    I'm great thanks! :hugs:

    How are you!? :jive:
    Posted from TSR Mobile
    Pretty good! Feeling rested :closedeyes: and still revising :jive:

    Any plans today? Happy 1st of May! Pinch punch, etc. etc. :mmm:
 
 
 
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