Convolution Help on tri(x,y) ** (step(x) * 1(y))

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The discussion revolves around performing a 1D convolution of a 2D function, specifically tri(x,y) ** (step(x) * 1(y)). The confusion arises from whether to ignore the 'y' components and simply convolve tri(x) with step(x). It is clarified that the exercise likely requires two separate convolutions, one with respect to x and another with respect to y. The integrals for these convolutions are provided, indicating that y can be treated as a constant in the first integral and x in the second. Ultimately, it is revealed that the function tri(x,y) can be separated into two 1D convolutions, simplifying the problem significantly.
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Homework Statement
Evaluate and sketch the 1-D convolutions:
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tri(x,y) ** (step(x) * 1(y))
I have some confusion about this question.

I am asked to do the 1D convolution of a function that is clearly 2-dimensional

tri(x,y) ** (step(x) * 1(y)) where ** is the convolution.

Furthermore my professor is not available for questions (have tried). I'm wondering if I simply ignore the bits of 'y' and convolve

tri(x) ** step(x)

or if there's something I'm missing. I don't have the text yet (on order - Easton's "Fourier Methods in Imaging") and the library doesn't have a copy either. Also if anyone happens to know the name of the function 1(y) I'd be most grateful.
 
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I think the exercise means to do two different convolutions, one with respect to x and one with respect to y.(it says evaluate and sketch the 1-D convolutions).
So first calculate the integral
##\int tri(t,y)step(x-t)1(y)dt## (y is effectively a constant for this calculation) and then the integral ##\int tri(x,t)step(x)1(y-t)dt## (now x is considered to be a constant).
 
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I found out what is going on. Turns out that since tri(x,y) => tri(x) * tri(y) the equation is separable and can be written as two 1d convolutions like

(f(x) ** h(x)) * (f(y) ** h(y))
 
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Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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