High School Is dy/dx of x2+y2 = 50 the same as dy/dx of y = sqrt(50 - x2)?

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The discussion centers on whether the derivative dy/dx of the equation x² + y² = 50 is equivalent to that of y² = 50 - x². It concludes that they are not the same, as implicit differentiation of x² + y² = 50 yields dy/dx = -x/y. The participants emphasize that dy/dx represents the derivative of y with respect to x, not a direct operation on equations. They clarify that both equations are equivalent in terms of their solutions, but differentiation must be approached correctly. The key takeaway is that implicit differentiation should be applied to find dy/dx without needing to solve for y explicitly.
Blockade
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For implicit differentiation, is dy/dx of x2+y2 = 50 the same as y2 = 50 - x2 ?

From what I can take it, it'd be a no since.
For x2+y2 = 50,
d/dx (x2+y2) = d/dx (50) --- will eventually be ---> dy/dx = -x/y

Where,
y2 = 50 - x2
y = sqrt(50 - x2)
dy/dx = .5(-x2+50)-.5*(-2x)
 
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Derivatives (dy/dx) are operators on functions, not on equations. Your post is meaningless.
 
Blockade said:
For implicit differentiation, is dy/dx of x2+y2 = 50 the same as y2 = 50 - x2 ?
You don't "take dy/dx of" anything. dy/dx is the derivative of y with respect to x. The two equations above are equivalent, meaning that any (x, y) pair that satisifies one equation also satisfies the other equation.

If you differentiate both sides of either equation with respect to x, you should be able to find dy/dx.
Blockade said:
From what I can take it, it'd be a no since.
For x2+y2 = 50,
d/dx (x2+y2) = d/dx (50) --- will eventually be ---> dy/dx = -x/y

Where,
y2 = 50 - x2
y = sqrt(50 - x2)
There's no need to solve for y. Just differentiate y2 implicitly with respect to x.
Blockade said:
dy/dx = .5(-x2+50)-.5*(-2x)
 
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Blockade said:
For implicit differentiation, is dy/dx of x2+y2 = 50 the same as y2 = 50 - x2 ?

From what I can take it, it'd be a no since.
For x2+y2 = 50,
d/dx (x2+y2) = d/dx (50) --- will eventually be ---> dy/dx = -x/y

Where,
y2 = 50 - x2
y = sqrt(50 - x2)
dy/dx = .5(-x2+50)-.5*(-2x)
Sub -in the value of y in the first equation ( and cancel out the twos on the second one).
 

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