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# Algebra 2

HayleyBoo

1
Fri 1 Apr, 2016 06:15 am
@maxdancona,
Yes, Im learning about compositions of functions. Sorry I responded so late!!
This very much confuses me! I'm a junior in high school & I should know this, but alas.. I don't !
I hope that you guys will have some patience's with me, for a need more assistances with others.. ( I have an IEP)..
fresco

1
Fri 1 Apr, 2016 10:02 am
@maxdancona,
I'm not convinced, but you obviously are. IMO and experience, the majority of the population of learners, would not care less what 'an accurate' answer was to the egg situation...only in 'the trick' about the wrong answer 8 ! You will be left with the small minority of proto-mathematicians/engineers/scientists who would get where they are going irrespective of particular pedagogical methods. Their only real problem is survival of the social stigma of 'being called a nerd'!

Many years ago somebody advised me that teaching could be likened to 'casting pearls before swine'....the'pearls' often being 'artificial' but 'the swine' usually 'real' ! My final comment on this thread is the suggestion that you re-examine the pearls you are casting here with respect to that advice.

0 Replies

maxdancona

1
Fri 1 Apr, 2016 04:11 pm
@HayleyBoo,
No problem Hayley, if you want to walk through it with me... I am very patient. My goal will be to help you to understand how functions work. Once you understand that, the rest is pretty straightfoward.

f(x) = -2x + 3

Think about this function as a machine. You put in one number and you get out another number. We will call the in number the "input" and we will call the out number the "result".

We can write this in math (like we did above) or we can write the same machine in words

For the function named 'f', you get the result by multiplying the input number by -2 and then adding three

You can try either one of these forms (they work the same)... and I will let you try.

If you put a number 1 as the input to the machine (function), what will the result be?
If you put a number 3 as the input to the function, what will the result be?
If you put a number 0 into the function, what will the result be? (I am rewording the question a bit but is the same question).

You can ask this type of question by simply saying f(2) = ? ... but it helps to think about what you are doing is putting some value into this function and getting a result.