Solving for p and q: A Graph of 5 = cos 0 and 1 = cos 180

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In summary, the problem is to find the values for integers p and q in the equation y = p + q cos x, given a graph of y = cos x with y-values of 5 at x = 0 and 1 at x = 180. Using the equations 5 = p + q and 1 = p - q, the solution is found to be p = 3 and q = 2.
  • #1
thomas49th
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Homework Statement



I have a graph of 5 = cos 0 and 1 = cos 180. The question is find the values for integers p and q
y = p + q cos x

p and q are integers

How do I go about doing this

Thx
 
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  • #2
Excuse me? I don't think anyone will understand that...5= cos 0? Not only is that not true..how you graph something like that is out of the question, similarly to the 1=cos 180. State the question more clearly please.
 
  • #3
sorry. I mean the graph cos x starts at y = 1 when x = 0 and goes into a bucket like shape. The graph I'm given is the same as y = cos x EXCEPT that it's when x = 0 y = 5 and when x = 180 y = 1... so the lowest value of y is 1 and it's highest is 5, if you see what i mean?

Thx
 
  • #4
thomas49th said:
sorry. I mean the graph cos x starts at y = 1 when x = 0 and goes into a bucket like shape. The graph I'm given is the same as y = cos x EXCEPT that it's when x = 0 y = 5 and when x = 180 y = 1... so the lowest value of y is 1 and it's highest is 5, if you see what i mean?

Thx

Ok, so when x = 0, then y = 5, it means that:
5 = p + q cos(0o) = p + q

When x = 180o, y = 1, that means:
1 = p + q cos(180o) = p - q

So you have 2 equations:
[tex]\left\{ \begin{array}{ccc} 5 & = & p + q \\ 1 & = & p - q \end{array} \right.[/tex]
From the system of equations above, can you solve for 2 unknowns, namely, p, and q?
Can you go from here? :)
 
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  • #5
similtaneous equations
p = 1 + q

so 5 = 1 + q + q
so q = 2
therefore p = 3

right?
 
  • #6
thomas49th said:
similtaneous equations
p = 1 + q

so 5 = 1 + q + q
so q = 2
therefore p = 3

right?

Perfectly correct. Congratulations. :)
 

FAQ: Solving for p and q: A Graph of 5 = cos 0 and 1 = cos 180

What do p and q represent in this equation?

P and q represent the x and y coordinates on the graph, respectively.

How do you solve for p and q?

To solve for p and q, you can use the trigonometric identity: cos (180 - x) = -cos x. In this case, you can rewrite the equations as 5 = cos (180 - p) and 1 = cos (180 - q). This means that p = 0 and q = 0. Therefore, p and q are both equal to 0.

What does the graph of 5 = cos 0 and 1 = cos 180 look like?

The graph of 5 = cos 0 and 1 = cos 180 is a straight line passing through the origin (0,0). This is because both equations reduce to p = 0 and q = 0, which is the point of intersection for a line passing through the origin.

What is the significance of solving for p and q in this equation?

Solving for p and q allows us to determine the exact values of the x and y coordinates on the graph, which can be useful in understanding the behavior and properties of the cosine function.

Are there any other solutions for p and q?

No, there are no other solutions for p and q in this equation. This is because the cosine function is periodic and repeats after every 360 degrees, so the only solutions for p and q are 0. However, if the equations were different (e.g. 5 = cos 45 and 1 = cos 225), there may be multiple solutions for p and q.

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