Understanding the Graph of an Equation | Calculus Help

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The discussion focuses on understanding the graph of the equation Y = (2X^2)/(9 - X^2) in calculus. The user is confused about identifying the positions of curves and has found three critical points: X = 0, X = -3, and X = 3. It is clarified that the derivative dy/dx = 36x/(9 - x^2)^2 is correctly derived, indicating that x = 0 is a point of horizontal tangency, while x = -3 and x = 3 are vertical asymptotes where the function is undefined. These asymptotes create three intervals on the number line, which correspond to the three distinct sections of the graph. Understanding these points is essential for accurately sketching the graph of the function.
Bandarigoda
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Hi everyone, I'm learning calculus at school. Recently I was taught this equation like. Y = (2X^2)/(9 - X^2)
So the teacher did all by himself. So I came home and now confused. I know there are 3 graphs(sorry if the word is not right ) so I was doing it again. And I'm stuck at where to get the position of curves.

I got,
X = 0 , X = -3, X= 3
They are 3 graph. So I couldn't figure out how to get more positions and draw it. Unfortunately I can't remember what teacher did 100% .
So someone please demonstrate it for me from the steps I have done.

Thanks
 
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I derived the functions and got their maximum /minimum
 
Here
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Bandarigoda said:
Hi everyone, I'm learning calculus at school. Recently I was taught this equation like. Y = (2X^2)/(9 - X^2)
So the teacher did all by himself. So I came home and now confused. I know there are 3 graphs(sorry if the word is not right ) so I was doing it again. And I'm stuck at where to get the position of curves.

I got,
X = 0 , X = -3, X= 3
They are 3 graph. So I couldn't figure out how to get more positions and draw it. Unfortunately I can't remember what teacher did 100% .
So someone please demonstrate it for me from the steps I have done.

Thanks

Your work for the derivative is correct: dy/dx = 36x/(9 - x2)2

Bandarigoda said:
I derived the functions and got their maximum /minimum
No, you differentiated the function and found the values for which f' = 0 or where the derivative is not defined.

If you set dy/dx = 0, the only solution is x = 0. The tangent line is horizontal when x = 0 (at the point (0, 0)).

dy/dx is undefined where the denominator is zero; namely, when x = 3 or x = -3. The original function is also undefined at the numbers. These turn out to be vertical asymptotes. The graph of the function tends to +∞ or -∞ on either side of these asymptotes.

Since there are two of them, they divide the number line into three intervals: (-∞, -3), (-3, 3), and (3, ∞). These intervals correspond to the three graphs you're talking about.
 
Hi, thank you very much Sir!
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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