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May 8th, 2006
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I need help urgently on Arrays and functions

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HI, I need to create a program which tests whether within a range given by the user, there exists an extreme of quadratic function (y=ax2+bx+c). The parameters (a,b,c) of this function are given by the user. I just started it but I have a problem in completing it. This is how far I can go.
#include <stdio.h>
int x;
int y;
int a,b,c;
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Re: I need help urgently on Arrays and functions

Quote originally posted by honeybleak ...
HI, I need to create a program which tests whether within a range given by the user, there exists an extreme of quadratic function (y=ax2+bx+c). The parameters (a,b,c) of this function are given by the user. I just started it but I have a problem in completing it. This is how far I can go.
#include <stdio.h>
int x;
int y;
int a,b,c;
Can you explain what you mean more clearly?
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iamthwee is offline Offline
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Re: I need help urgently on Arrays and functions

C++ Syntax (Toggle Plain Text)
  1. #include <stdio.h>
  2. int x;
  3. int y;
  4. int a,b,c; 
  5.  
  6. int main()
  7. {
  8.    // put your code here
  9.  
  10.  
  11.   return 0;
  12. }
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Re: I need help urgently on Arrays and functions

Do u need a complete program for this I justcreated one for calculating the roots of QUADRATIC EQUATIONS.
Replyto this if u need one or anyone else will copyit and use it.
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Cool Nanu is offline Offline
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Re: I need help urgently on Arrays and functions

No, that's not what's being asked for. honeybleak, do you know how to do the calculation on paper?
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Rashakil Fol is offline Offline
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Re: I need help urgently on Arrays and functions

see this article
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Re: I need help urgently on Arrays and functions

That link has nothing to do with finding the global extremum, which is located at -b/2a. (If a = 0 then there is no global extremum.)
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Re: I need help urgently on Arrays and functions

What does your avatar mean or represent Mr Rashakil? Remember the ancient dragon is no maths wizz kid :-)
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iamthwee is offline Offline
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Re: I need help urgently on Arrays and functions

I don't think it's a question of math, people just misinterpreted the problem (or had read the first misinterpretation of the problem). Why would I tell anybody what my avatar is?
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Re: I need help urgently on Arrays and functions

you have to check the bounds. i.e. if someone inputs the range ( -1 , 2 ). you should check the following.

let f(x) = ax^2 + bx + c .
check f(-1), f(2) and f(-b/2a).

since this is a quadratic it can be assumed that a != 0.

if you are looking for mins and max those are the only possible places they can occur ( local extrema f(-1), f(2) ) and a global extrema f(-b/2a).
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This thread is more than three months old

No one has posted to this discussion for at least three months. Please let old threads die and do not reply to them unless you feel you have something new and valuable to contribute that absolutely must be added to make the discussion complete. Otherwise, please start a new thread in this forum instead.
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