High School A relation which intercepts with....

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The discussion centers on the possibility of a function intersecting with both its derivative and indefinite integral at the same point, excluding the exponential function e^x. The user provides an example using f(x) = sin^4(x), which intersects at (0, 0) for f(x), f'(x), and ∫f(x)dx. They seek additional functions that exhibit this three-way intersection, ideally not limited to the origin. A suggested function is f(x) = (x-a)^n, where n > 1, which aligns with the user's criteria. The conversation highlights the exploration of mathematical relationships between functions and their derivatives and integrals.
Saracen Rue
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I am wondering if it's possible for a relation to intercept with both it's derivative and indefinite integral at the same location (not including e^x as it shares the same rule as both it's integral and derivative). This is also assuming the constant of the indefinite integral is equal to zero.

Basically;
Define f(x) where the solution to f(x) = f'(x) is the same as the solution to f(x) = ∫f(x)dx, f(x) ≠ e^x and c = 0
 
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##f(x) = f '(x)## is basically one way (among many) to define ##e^x## (up to a constant or the requirement##f(0)=1##).
What exactly are you looking for?
 
fresh_42 said:
##f(x) = f '(x)## is basically one way (among many) to define ##e^x## (up to a constant or the requirement##f(0)=1##).
What exactly are you looking for?
I'll give an example;
Let f(x) = sin^4(x). In this scenario, f(x), f'(x) and ∫f(x)dx all intersect the x-axis at (0, 0). Therefore, there is a three-way intersection between f(x), f'(x) and ∫f(x)dx at said point. I'm looking for other functions or relations which also have a three-way intersection between f(x), f'(x) and ∫f(x)dx. Preferably not at the origin, but I don't mind if they are.
 
How about ##f(x)=(x-a)^n## with ##n > 1##?
 
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fresh_42 said:
How about ##f(x)=(x-a)^n## with ##n > 1##?
Yes, that is an excellent example of what I meant. Thank you :)
 

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