How Do You Determine the Correct Boundaries for a Marginal Density Function?

[wuid]

Hi all

i have problem with my h.w , i think the question is related more to math than to probability, but I'm sure someone here will find how to help me

so i attached my solution with the question, i think i have difficulty to find the right boundaries of the marginal density function of X.

please have a look ,

thx in advance

 

[clamtrox]

Why are you trying to calculate the marginal distribution? Wouldn't it be easier just to integrate the full PDF in polar coordinates again?