Average change rate of a function #21: f(x)=1/2+3

Illvoices

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A linear function is given. (a) Find the average rate of change of the function between x=a and x=a+h . (b) Show that the average rate of change is the same as the slope of the line.

f(x)=1/2+3
 
Well, first off I'm guessing there's a small typo here and the given function is meant to be f(x) = (1/2)x+3. What you've posted is the horizontal line y = 7/2. That aside, what have you tried? Please share with us any and all work you've done on this problem, even if you know it's wrong. If you need a refresher on this material, you might try here.
 
hAverage change rate of a function #21

(1/2)x+3/100-100h = 1/2(100)+3 - 1/2(100h)+3/h

50+3-50h+3/h = h/h = h

the answer is 1/2 based on the appendix, but i dont understand how it got to there unless h is 1/2.
 
Okay, so what I think your (poorly formatted) working is showing is this:

\(\displaystyle \dfrac{\dfrac{1}{2}x+3}{100-100h} = \dfrac{\dfrac{1}{2}(100)+3 - \dfrac{1}{2}(100h)+3}{h}\)

Assuming the above is the correct interpretation of your work, I have a few questions. First, where did the number 100 come from? The problem you originally posted asked about the average rate of change between the points x=a and x=a+h. It appears as if you've somehow transformed that into the interval between the points x=100 and x=100h. By what basis have you concluded this? Second, by what basis have you concluded that the denominator, being 100-100h, is equal to h?
 
Okay, so what I think your (poorly formatted) working is showing is this:

\(\displaystyle \dfrac{\dfrac{1}{2}x+3}{100-100h} = \dfrac{\dfrac{1}{2}(100)+3 - \dfrac{1}{2}(100h)+3}{h}\)

Assuming the above is the correct interpretation of your work, I have a few questions. First, where did the number 100 come from? The problem you originally posted asked about the average rate of change between the points x=a and x=a+h. It appears as if you've somehow transformed that into the interval between the points x=100 and x=100h. By what basis have you concluded this? Second, by what basis have you concluded that the denominator, being 100-100h, is equal to h?

actually the h at the end was on top and i would like to know how'd you get to write the equation that good with the fraction line and all
 
This forum has a built in LaTeX parser, to facilitate greater of ease of "writing in math," as it were. Using it is fairly simple. For instance, if you wanted to write a faction, you would simply write in your message:

Code:
[tex]\dfrac{numerator}{denominator}[/tex]

which would then produce:

\(\displaystyle \dfrac{numerator}{denominator}\)

You can "nest" fractions as well by placing one inside another. The code for the left-hand side of the equation in my previous post was made this code:

Code:
[tex]\dfrac{\dfrac{1}{2}x+3}{100-100h}[/tex]

\(\displaystyle \dfrac{\dfrac{1}{2}x+3}{100-100h}\)

You can find a decent guide on LaTeX here.

LaTeX can be a helpful tool, but it's not really going to immediately help you solve the problem you were tasked with. I asked a few questions in my last post to clear up exactly what your reasoning was, so as to know how best to proceed. Did you see those questions?
 
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