[BlindMath] Average Rate of Change pr

[Sabra Ewing]

, perhaps you do not have an understanding of pre-calculus. You could be confusing the person which is the only reason I mention it. Look at Susan's answer. That is correct.

Sabra Ewing

> On Aug 19, 2018, at 4:06 PM, Doug and Molly Miron via BlindMath <blindmath at nfbnet.org> wrote:
> 
> Good day Susan,
> 
> 
> I think all of us that previously responded to Elise's query agree that the function in question is f(x)=x^2 - x-+1.  We took somewhat different approaches to how to find the average rate of change, but we mostly agreed on the result.  Notation when writing in ASCII is an issue, and some of us have too much experience to keep it down to a novice level, unfortunately.  I would like to hear from Elise whether any of this has been useful to her.
> 
> 
> Regards,
> 
> Doug Miron
> 
> 
>> On 8/19/2018 4:37 PM, Susan Jolly via BlindMath wrote:
>> These answers got me confused and I've studied a lot of calculus.  But remember this is pre-calculus.
>> 
>> First the average rate of change of a function over a certain interval is not the same as the average of the function itself over that same interval. Finding the average rate of change just requires a simple formula whereas find the average of the function is something more complex one will learn about in calculus.
>> 
>> Remember that the notation f(x) means a general formula for calculating y if you know x whereas f(x_1) or f(x_2) means the value of y at the specific points x_1 or x_2.
>> 
>> The formula for the average rate of change defined to be
>> a = [f(x_2) - f(x_1)]/(x_2 - x_1)
>> 
>> It would be nice to understand why this formula is correct but first you should memorize the formula and be able to use it.
>> 
>> In this  case the function is f(x) = x^2 - x + 4.
>> 
>> The value of this function when x = 2 is 6.
>> The value of this function when x = 6 is 34.
>> (Being able to plug numbers  into formulas and find the result is one of the things you are supposed to be comfortable with.)
>> 
>> so a = (34 - 6) / (6 - 2 ) = 28/4 = 7.
>> 
>> HTH,
>> Susan Jolly
>> 
>> _______________________________________________
>> BlindMath mailing list
>> BlindMath at nfbnet.org
>> http://nfbnet.org/mailman/listinfo/blindmath_nfbnet.org
>> To unsubscribe, change your list options or get your account info for BlindMath:
>> http://nfbnet.org/mailman/options/blindmath_nfbnet.org/mndmrn%40hbci.com
>> BlindMath Gems can be found at <http://www.blindscience.org/blindmath-gems-home>
>> 
> 
> 
> 
> _______________________________________________
> BlindMath mailing list
> BlindMath at nfbnet.org
> http://nfbnet.org/mailman/listinfo/blindmath_nfbnet.org
> To unsubscribe, change your list options or get your account info for BlindMath:
> http://nfbnet.org/mailman/options/blindmath_nfbnet.org/sabra1023%40gmail.com
> BlindMath Gems can be found at <http://www.blindscience.org/blindmath-gems-home>