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anonymous
 5 years ago
(d^2y/dx^2) of (dy/dx)=y^2(62x)
anonymous
 5 years ago
(d^2y/dx^2) of (dy/dx)=y^2(62x)

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amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0you want the derivative of the derivative :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0or the 3rd derivative..... hard to tell

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0implicit or solve for y

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i dont know what d^2y/dx^2 means

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0d^2y/dx^2 is just the 2nd derivative of an equation, for example: y = 2x^2 dy/dx = 4x d2y/dx2 = 4

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh, so i am just finding the 3rd derivative pretty much?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0thats what I think..... and youll have to use implicit stuff y'=y^2(62x)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I forgot what implicits are):

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0implicits are the same steps as normal derivatives except you "keep" the implicits in the equation to factor out in the end...like this: x+xy = 4 d(x) + d(xy) = d(4) dx + dx y + x dy = 0 solve for dy

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0dy = dx dx y//x ; dx = 1 so.. dy = 1 y //x

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0y' = y^2(62x) y'' = y' 2y(62x) + y^2(2x)x' ; x' = 1 y'' = y' 12y 4xy  2xy^2 is what I get

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0how do i find the derivative of y, like x's you bring the exponent to the front? like if it says y^2 what do i do?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0watch what we do with derivatives :) d (2x^3) dx (6x^2)  =  dx dx now dx/dx = 1 usually so we omit it.... right?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0d (y^2) dy (2y)  =  dx dx dy/dx IS y' or the first derivative. it doesnt cancel so we just keep it in the equation as y'

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so it will be 2y y' ?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0thats absolutely correct :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0after your done ; substitute the value for y' into the finished work

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so if i do this problem y^2(6x) i have to do 2y y'(62x)(2)?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0i find it ironic that they title me "superhero", and your named "helpless" lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Hahaha, that is funny!

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0y^2(6x) is simply the product rule with a little extra stuff jambed between the lines....

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0rl' + r'l is all it amounts to

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0r = y^2 r' = y' 2y l = (6x) l' = 1

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh! so it'll be 2y y'(62x)+y^2(2)? or am i going off on the wrong track with the y's again?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0squish it all together and simplify

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sorry the problem was actually y^2(62x)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0yes.... i missed the 2 from up top...but yes...thats it

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0you already know what y' equals, it was the original problem right?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0I think they ask for y'' and give you y'=yadayada..... so this would be the final step :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0No y'=y^2(62x) so then 2y y'(62x)+y^2(2) is y"

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so i just leave it like that?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0you can...but just be aware that any answers on a test might be written in the full expanded form.

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0just replace the y' with y^2(62x) and work the math :) 2y (y^2)(62x)(62x)+y^2(2)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.02y^3(3624x +4x^2) 2y^2

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0and so on and so forth...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0how'd you get this part?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0lets step thru this... we found y'' right? what is it?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0nevermind i think i get it because you did (62x)(62x) to get (3624x +4x^2)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0y' was the only variable we new the "value" of, so I just replaced it and did the math

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0'& that's the answer right? So if it gives me a point, i would just plug the values in for my x and y? then solve for that?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0thats right, with implicits they have to give you a way to know the x and y values.....

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay i think i got it. But part b says to find y=f(x) by solving (dy/dx)=y^2(62x) using the initial condition f(3)+1/4

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0you gotta di the inegral to find F(x) ;)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so i do the anti derivative of y'?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0jsut "cross multiply" to split the variables...... yeah

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0dy y^2(62x)  =  dx 1

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0[S] 1/(y^2) dy = [S] 62x dx

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0its my lazy version of the elongfated "S" symbol they use for the integral/anti derivative stuff

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0i loathe the "equation" editor, slows down the computer with it trying to decode all the stuff

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Hahahahah, i get you!(: how did you get that from cross multiplying though?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0this is our original problem right? dy y^2(62x)  =  dx 1 we cross multiply to get the "y" stuff to one side and the "x" stuff to the other so we can inegrate them separately

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0if you havent read ahead past the "antiderivative" jargon yet... then you probably are wondering if I can do that :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Okay so when once i get them separated, is 1/y^2 lny^2?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0now now..make it easier on yourself...1/y^2 = y^2

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0[S] y^2 dy = [S] (62x) dx

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0y^1/1 = 6x (2)x^2/2 + C

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0why is it 2x^2/2 why is it divided by two and not just x^2?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0.... its a place holder so I dont lose track of it and make more mistakes than ususal :) 2x becomes 2x^2/2 simplify .... x^2

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0tuen each side of..to the reciprocals.. to get "y" on top

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0y = 1 // x^2 +6x + C get rid of the () by dividing both sides by 1 y = 1 // x^2 6x  C and we should have it

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0i took typing class and passed....honest :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0what does the // mean? sorry, i dont know how to do all this math anywhere but on paper.

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0I use that to mean the there is a larger fraction bar that separates the top and bottom, it just means that everything before it is on top and everything after it is on bottom. otherwise id look like this: 1/x^2 6x C which can be misleading....

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0plug in your inital values and lets solve for "C" :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so is it 1/4=(1/(x26x+c))

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0if the i.c is f(3)+.25

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0x^2 6x +C = 4 x^2 6x 4 = C right?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0x = 3 and y = 1/4 yes

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.09  18  4 = C C = 13 if I did it right :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0where is the 4 coming form?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0lets see if: it works for us :) 1/4 = 1/(9 18 13) ...you put it there with the 1/4......right?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay waitso the equation is 1/4=(1/(x^26x+c)?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0yep, cross multiply or jsut flip them both over or jsut notice that the bottom parts need to match up and equal each other

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay so when i plug in the point i get 1/4=918+c?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0no...lets start at the beginning of this: 1 y =  x^2 6x +C f(3) = .25 = 1/4 1 1  =  4 (3)^2 6(3) +C 4 = 9 18 + C

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so because 1 is on top on both sides i can cancel it?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0....not "because" the 1 is on top..... but yeah. we are wanting to make that bottom right hand side the same number as the bottom of the left hand side. We can either cross multiply and get them both on top. We can flip them over to their reciprocal counterparts (which is what I did). Or, we can simply notice that the only thing that matters in this equation is that the bottom numbers have to equal and we can ignore anything else :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Okay i got it now. Now i see how you got C=13 (:

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay! Thank you so much!:D

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0did we solve our problem? because I am wondering if that +C changes if we are looking for C.... better get 2 answers so you can double check yourself

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0wait how do i find C?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0just change +C to C and get an answer for it.....

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0wouldnt it just be 13?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0dunno, my brains not giving me an answer lol 4 = 9 18  C C = 9418 C = 5  18 = 13 were good.....

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so i put plus and minus 13 as my answer and my problem is completely answered?(:

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0+c = 13 c = 13 = 13 c = 13

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay got it! Thank you for your help!(:

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I might be back tomorrow, hahahah.(;
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