Results 1 to 8 of 8

Math Help - graph to solve

  1. #1
    Newbie
    Joined
    Dec 2009
    Posts
    5

    graph to solve

    cheyenne, wyoming has a latitude of 41 degrees north. At this latitude, the position of the sun at sunrise can be modeled by D=31sin((2pie/365)t-1.4) where t is the time K(in days) and t=1 represents january 1. In this model, D represents the number of degrees north or south of due east that the sun rises. Use a graphing utility to determine the days on which the sun is more than 20 degrees north of due east at sunrise.

    can't figure this one
    thanks for the help!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member bigwave's Avatar
    Joined
    Nov 2009
    From
    honolulu
    Posts
    580
    Quote Originally Posted by belloway View Post
    cheyenne, wyoming has a latitude of 41 degrees north. At this latitude, the position of the sun at sunrise can be modeled by D=31sin((2pie/365)t-1.4) where t is the time K(in days) and t=1 represents january 1. In this model, D represents the number of degrees north or south of due east that the sun rises. Use a graphing utility to determine the days on which the sun is more than 20 degrees north of due east at sunrise.

    can't figure this one
    thanks for the help!
    your equations is a little bit ambiguous is this what you mean:

    D=31\sin{\left(\frac{2\pi}{365}\right)}\left(t-1.4\right)

    if you are solving for t then rewrite the equation to t= and plug in 20
    for D
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor

    Joined
    Apr 2005
    Posts
    16,259
    Thanks
    1800
    Quote Originally Posted by belloway View Post
    cheyenne, wyoming has a latitude of 41 degrees north. At this latitude, the position of the sun at sunrise can be modeled by D=31sin((2pie/365)t-1.4) where t is the time K(in days) and t=1 represents january 1. In this model, D represents the number of degrees north or south of due east that the sun rises. Use a graphing utility to determine the days on which the sun is more than 20 degrees north of due east at sunrise.

    can't figure this one
    thanks for the help!
    This problem tells you exactly what to do! Have you done that? Have you put this function, y= 31 sin(\frac{2\pi}{365}x- 1.4) into a "graphing utility" (such as a graphing calculator), as well as the function y= 20, to see where the first is above the second graph? The whole point of suggesting you use a "graphing utility" is that they do not expect you to solve that equation.
    Last edited by HallsofIvy; January 3rd 2010 at 02:13 AM.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    12,063
    Thanks
    902
    screenshots ...
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Dec 2009
    Posts
    5

    Thanks!

    Thank You so much for all your help! I really appreciate it!
    Follow Math Help Forum on Facebook and Google+

  6. #6
    MHF Contributor

    Joined
    Apr 2005
    Posts
    16,259
    Thanks
    1800
    Okay, what answer did you come up with?
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Newbie
    Joined
    Dec 2009
    Posts
    5
    Days 133 to 233. I know it's right because it was in the back of my book. I hasd the answer just didn't know how to get to it. Thanks again.
    Follow Math Help Forum on Facebook and Google+

  8. #8
    Newbie
    Joined
    Dec 2009
    Posts
    5
    Days 133 to 233. I know it's right because it was in the back of my book. I hasd the answer just didn't know how to get to it. Thanks again.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Solve and graph?
    Posted in the Algebra Forum
    Replies: 6
    Last Post: July 25th 2009, 10:30 PM
  2. solve and graph
    Posted in the Algebra Forum
    Replies: 4
    Last Post: June 19th 2007, 12:37 PM
  3. solve and graph
    Posted in the Algebra Forum
    Replies: 1
    Last Post: July 18th 2005, 12:20 AM
  4. solve and graph
    Posted in the Algebra Forum
    Replies: 1
    Last Post: July 13th 2005, 10:12 PM
  5. Replies: 2
    Last Post: June 24th 2005, 02:37 AM

Search Tags


/mathhelpforum @mathhelpforum