Implicit differentiation? implicit integration?

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
1 reply · 3K views
user01
Messages
16
Reaction score
0
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?
 
Physics news on Phys.org
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.