Implicit differentiation? implicit integration?

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Implicit differentiation allows for finding the derivative of y with respect to x in equations like x^2 + y^2 = 7, resulting in dy/dx. The discussion raises the question of whether implicit integration exists, particularly for linear terms in y, demonstrating that integration can yield results similar to differentiation. However, for non-linear terms in y, implicit integration becomes complex, as it relies on the chain rule, which does not allow for straightforward reversal in integration. The key challenge is that implicit integration requires the derivative to already be present in the integral, limiting its applicability. Overall, while implicit differentiation is well-defined, implicit integration is more nuanced and often requires substitution methods.
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We have implicit differentiation:
i.e. x^2 + y^2 = 7
-> 2x +2y(dy/dx) = 0.
and solve for dy/dx gives you the derivative of y with respect to x

However, is there not implicit integration?

for terms linear in y,
i.e. x^2 + y = 7
-> X^3/3 +int(y) = 7x + K,
and solve for int(y) to get the intergral of y with respect to x

But what about terms non-linear in y?
 
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Implicit integration is basically the use of the "chain rule": if you have y2 then d(y2)/dx= d(y2)/dy dy/dx= 2y y'. Unfortunately, you cannot, in general go the opposite way: using the chain rule to differentiate you calculate the expression, dy/dx, that must be multiplied, while integrating it has to already be in the integral. "Implicit" integration is basically "substitution" which only works if the derivative of the function substituted is already in the integral.
 

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