I Is It Possible? Solving Calculus Questions with Ease

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Calculus questions can often seem simplified by treating derivatives as fractions, but this is not mathematically accurate. The notation for derivatives, such as dθ/dt, is not a true fraction, meaning dt cannot be canceled in a strict sense. However, in practice, this "cancellation" resembles the chain rule, allowing for easier manipulation of expressions. Historical mathematicians have shown that treating differentials as fractions can be useful, despite the lack of formal justification. It is important to adjust integral bounds accordingly when changing the variable of integration.
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Hi, just wondering if that's possible in calculus.
(See the attachment)
 

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NODARman said:
TL;DR Summary: .

Hi, just wondering if that's possible in calculus.
(See the attachment)
What you wrote was essentially correct. But...

In reality? No. The derivative notation ##\dfrac{d \theta }{dt}## is not actually a fraction so you cannot cancel the dt's.

However, in practice you can "cancel" the dt's. It's a similar effect to the chain rule: ##\dfrac{d \theta }{dx} = \dfrac{d \theta }{dt} \cdot \dfrac{dt}{dx}##. Again, there is no real cancellation, but it appears that way.

Mathematicians in the 1800s spent a great deal of time showing how you can treat a differential element as a fraction. Most of the time you can get away with it.

-Dan
 
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Technically the bounds on the integral need to change to ##\int_{t(0)}^{t(2\pi)}## if you are integrating wrt ##t##.
 
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