Does anyone understand the graphs at all?
Yes, you find the derivative of f(x), I'm assuming that #7 is f(x) = x^2, 8 is x^3, 9 is cosx, and 10 is x^4. So instead of plugging a point you just put in x's and h's. Then, you'll have an equation at the end. Say the equation is 2x. You would look for the graph of 2x (letter b) and make it the answer of the corresponding number. Does anyone know how to do number 9 though? I can't figure out how to get h out of cos(x+h)-cos(x)/h
Psych, number 10's regular function graph is actually f(x) = something . . don't know what
For number 1
all u do is is plug in f(2) into the equation and have the equation = 5 right?
I'm confused on number one, I think you plug in f(2) for (x) and have the equation = 5, but I don't think it gives you the right answer.
for number one a. use the fact that the derivative of a point is the slope at that point. So, you have the slope of a line and a point is passes through (f(2)=3 is the point)
b. look back to the last section of ch. 2
Thanks Court, that makes more sense now!
how do you do number 15 if they don't give you an actual equation?
how do you do #17 ?
Dan for #15, i think they're asking us to estimate.
Dan, for #15 you look at the graph, notice it is going from convex to concave. Since you know the slope is 0 aroung Junuary 1 and July 1 the middle of that has to have the greatest slope. And than to find the slope take the y values from March 15-April 15 and divide it by the x values, the number of days in a month (30).
If you understand a., i think b and c should become a little easier.
Heli, for #17 a. you look at the top graph and see where its y-values are the highest (40,2200) and the lowest (150,100). After that look at the bottom graph, find those two x-values and notice where they are located (what is the y-value).
b. look at the bottom graph first. notice where the highest part of the graph is (20,40) and the lowest part of the graph (65,-55). than look at the top graph, use the x-values you found to figure out what the y-values of the top graph are and those would be your answers.
got it! thanks!
What is NDER...
NDEr is the numerical derivative of f. it shows this on page 108. for # 27 how is the answer tan(x)?
A way of estimating the derivative of something within 3 decimal places. It stands for numerical derivative and it's the limit of f(a+h) - f(a-h)/2h as h approaches .001
If you see NDER (2x^2, 3) it means the numerical derivative of 2x^2 when x = 3. Just plug in x and h (.001)
Haha, I need to refresh my page, sorry Andrew
For #5 I tried using the quotient rule but then I ended up getting a really weird answer. Did anyone else use the rule and get the right answer??
Ooops nvm. I didn't apply the rule correctly. i got it now
for #15, you use the quotient rule right? Or do you have to use the product rule first for the top, then the quotient rule?
Yeah so i tried 11 twice and for some reason i came up with two different answers (like for a and b) both times... is there anyway i can just like see the process someone else used?
Kelsey: Yea for #15 i simplified the top first and then i used the quotient rule.
Whitney: What did u get for A and B??
Vashista, Okay that's what I did, but i got a different answer than what the book says you're supposed to get... did thta happen to you? or did i mess up somewhere? Cause i did it twice... ?
Ohh srry. i didn't check the answer yet.
hmmm. Im gonna try it again and then ill try it the other way
p.s. I'm so sorry I just realized I spelled your name wrong, sorry Vasishta
LOL its ok
Yea i have no idea for #15.
its not working either way ...
Yeahh, and I'm having the same problem for 19 also... Does anyone else know how to do it if its not those?
For number 15, multiply the numerator out and get x^3-1, still divided by the denominator x^3. You have a achoice from there to either rewrite the equation as two terms: 1-x^-3 and take the derivative of it OR you can leave it as a quotient and apply the quotient rule. Either way you will ge the same result.
Nice job blogging guys! Keep it going!
The same concept applies for #19. You may choose to multiply the numerator out and then do the same for the denominator and then apply the quotient rule. Be sure to list what you call u, v, u', v' so that making corrections will be made easy.
how do you do #15 and #16 from derivative worksheet ?
Heli: For number 15 u have to use the power rule. So u would have
3ax^2 + 2bx + 1.
how do you do #15 from 3.4 ?
can anyone explain how to do 28 29 and 31? i get everything for the most part but how to do those?
For 28, It's jsut writing like explaining why each graph is which. It's all derivatives, and if you remember the power rule you know which graph looks like a cubic, parabola, and linear. The cubic has the highest power so it is the first graph. It correlates with position, velocity and acceleration. So like which one of those is first, then its derivative, then the derivative of that.
Dan, for 29, if you look at C, you know that the derivative of C looks like B, and the derivative of B looks like A.
C is position (x^3)
B is velocity (2x^2)
A is acceleration (4x)
Can anyone explain the chain rule because I am so lost
for # 24 for 3.6, do we just use the chain rule? or is it like the product rule for both parts of the equation?
For #24 you use the chain rule just like you did in #21.
so for number 17 can someone explain it? having y as the argument is confusing me the problem's x= tan y
For number 6 on the worksheet.
Should i leave the 4x^3y on the left or subtract it over?
can someone please tell me what assignment we're on? i was out sick today
sam, 3.8 p. 162, 1-17 odd.
This might be a really stupid question, but how do we know when to use the formal or alternate derivative definition?
Just like in one of our warm ups today. It will tell you in the instructions if you have to use the formal derivative definition.
But what if it doesn't? And don't you use the alternate one for points?
Mrs. Johnson teaches math at Metea Valley High School in Aurora, IL.
Ap Ab Calculus
H Algebra 2 Trig
H Pre Calculus
Regular Pre Calculus