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Posers and Puzzles

Posers and Puzzles

  1. 10 Feb '04 12:38
    given:
    y<-3(X-4)+5
    y>0
    and
    A=X^2+Y^2
    find the largest possible value of A.
  2. Standard member TheMaster37
    Kupikupopo!
    10 Feb '04 13:22
    Originally posted by fearlessleader
    given:
    y<-3(X-4)+5
    y>0
    and
    A=X^2+Y^2
    find the largest possible value of A.
    289/10
  3. 11 Feb '04 03:42
    Originally posted by fearlessleader
    given:
    y<-3(X-4)+5
    y>0
    and
    A=X^2+Y^2
    find the largest possible value of A.
    i am not sure that this makes sense as written.
    if y &lt; -3(x-4) +5, y will be positive for any x &lt; 17/3.
    since x can be arbitrarily large negative and satisfy the conditions, A has no maximum.
  4. 12 Feb '04 16:24
    Originally posted by BarefootChessPlayer
    i am not sure that this makes sense as written.
    if y < -3(x-4) +5, y will be positive for any x < 17/3.
    since x can be arbitrarily large negative and satisfy the conditions, [b]A has no maximum
    .
    [/b]
    your right, typo.
    should read y&lt;-3X^4=5

    the point of this thread is that i to see if anyone knows how to find the maximum of nonlinear systems of inequalities.
  5. 12 Feb '04 22:44 / 2 edits
    Originally posted by fearlessleader
    your right, typo.
    should read y<-3X^4=5

    the point of this thread is that i to see if anyone knows how to find the maximum of nonlinear systems of inequalities.
    did you mean &quot;y&lt;= 3x^4=5&quot;?
    the equation you gave has no real solutions. if you accept the above, the possible values for x are: (5/3)^0.25, its negative, and those times i.
    if that's the case, any y less than (5/3)^0.25 would be adequate, and thus you'd have no maximum for A again since now y can go large negative.
    hope we can solve this one!
  6. 18 Feb '04 18:17
    Originally posted by BarefootChessPlayer
    did you mean "y<= 3x^4=5"?
    the equation you gave has no real solutions. if you accept the above, the possible values for x are: (5/3)^0.25, its negative, and those times i.
    if that's the case, any y less than (5/3)^0.25 would be adequate, and thus you'd have no maximum for A again since now [b]y
    can go large negative.
    hope we can solve this one![/b]
    oops! i missed that y must be positive.
    now maybe i can come up with a solution.
    sorry!