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anonymous
 5 years ago
I need help finding the equation of a sine function, I know (.75,0) to (.75,0) is one period and (.75,0) to (2.25,0) is another so based on that I was able to solve for "b" by applying the equation Period = 2pi/b so in that case 1.5=2pi/b, and therefore b=4.189, im stuck finding "a" and if there was any horizontal shift left or right, or any vertical shift up or down.
anonymous
 5 years ago
I need help finding the equation of a sine function, I know (.75,0) to (.75,0) is one period and (.75,0) to (2.25,0) is another so based on that I was able to solve for "b" by applying the equation Period = 2pi/b so in that case 1.5=2pi/b, and therefore b=4.189, im stuck finding "a" and if there was any horizontal shift left or right, or any vertical shift up or down.

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amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0so one period is 1.5 right? the other is 1.5 right?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.02pi  = 1.5; w = 2pi/1.5 right? w

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0without knowing anything more about the wave, or the graph there is no wayto determine the amplitude

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0since y=0 when the period happens we can assume its not lifted

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0since it is symetric about the orgin it aint shifted either

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0well, can I give you the rest of the points? it's a sine function essentially but with changing amplitude and period so my teacher suggested first getting the equation for the maximum values and then for a period piece and adding the two together does that make sense?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0giving all the information to a question is usually a good way to get an informed answer ;)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hahha ok one second and I will type the points out.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0(.75,0,) ...(.5, .7906) ....(0,0) ..... (.25, .90461),.... (.5, .94868) ....(.75, 0) ...(1, 1.039),... (1.25, 1.088) ...(1.5,0).... (1.75, 1.1915) .....(2,1.2471) and (2.25, 0)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0(0,0) use sine and no phase shift

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0how did you figure "a" as .75?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh because i was wrong. sorry

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0range from .75 to 2.25 yes?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i have to write hold on

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0range has length 3 yes?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so you need 1.5 out front

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so it will have range of length 3

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0then it goes from .75 to 2.25 so at the end you will need to add .75

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0this will take you from  .75 when the function is 1 (or rather 1.5) up to 2.25 when the function is 1 (or 1.5)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so far we know it looks like \[y= 1.5 sin(___) +.75\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0now we have to figure out what goes inside.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i meant \[y=1.5sin ( ?)+.75\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0period = 2pi/b and period we found was 1.5 right? so solve for b and its 4.189

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0that takes care of period yes?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0wait let me check hold on

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh no i am all messed up. i had the range at 3 but that is wrong wrong wrong. the range goes from smallest y value to biggest. what is the smallest y value?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok here maybe I can explain it better because I am trying to break this up as my teacher suggested, the full graph of what I need the equation for looks like the green graph on this link: http://www.google.com/imgres?imgurl=http://fan.lib.ru/img/z/zharow_a/evolution_continues/majatnik_kachajasx_bez_trenija.jpg&imgrefurl=http://fan.lib.ru/z/zharow_a/evolution_continues.shtml&usg=__uANt4T4noENBPROlSIgJEg9idI=&h=253&w=787&sz=51&hl=en&start=0&zoom=1&tbnid=L3R1ovN3yt9ifM:&tbnh=67&tbnw=208&ei=2RDkTc2gDsb00gHgms2cDg&prev=/search%3Fq%3Dgrowing%2Bamplitude%26um%3D1%26hl%3Den%26biw%3D1080%26bih%3D535%26tbm%3Disch&um=1&itbs=1&iact=hc&vpx=74&vpy=231&dur=243&hovh=127&hovw=396&tx=210&ty=90&page=1&ndsp=15&ved=1t:429,r:5,s:0&biw=1080&bih=535

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0does that link work if not i can find another

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0http://www.ltcconline.net/greenl/courses/204/appsHigherOrder/forcedVibrations.htm

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0that links better scroll down to the graph, see it?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh man i was way way off base. the last graph?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0where it says y=tsin(10t)? that graph

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0not the graph at the very bottom, where it says y=tsin(10t)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yeah so thats the shape of what I am working with and I given the following 12 points: (.75,0,) ...(.5, .7906) ....(0,0) ..... (.25, .90461),.... (.5, .94868) ....(.75, 0) ...(1, 1.039),... (1.25, 1.088) ...(1.5,0).... (1.75, 1.1915) .....(2,1.2471) and (2.25, 0)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh lord i have no friggin idea how to model this. let me think

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0well what my teacher recommended is finding the exponential equation of the maximum values and then finding the equation for a period piece like we were just trying to do and then adding the two functions together if that makes sense if not we can try any other way yoou can come up withh

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0well there is no exponential part of the picture you just sent. that is the last graph

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0if you connected just the maximum values it is..

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0are you looking at the right graph its the graph right before "Forced Vibrations with Damping"

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i have to confess that i really have no idea how to do this
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