The discussion revolves around the integral ∫2/(√(1-9x^2))*dx, focusing on the appropriate choices for u and du in the context of u-substitution. The subject area pertains to calculus, specifically integration techniques.
The discussion has progressed with some participants offering guidance on potential substitutions and derivatives. There is an acknowledgment of the need to show work, and one participant expresses satisfaction after receiving help with identifying u and du.
Participants are navigating the constraints of needing to demonstrate their work while grappling with the complexities of u-substitution in integration. There is an emphasis on understanding the process rather than simply arriving at the answer.
neshepard said:It's not a short cut in the sense of ∫sinx=-cosx, just from working the problem, I see that in the equation I take the numerator,2, and pull it out, plus I know that 1/(1-x^2) = sin^-1(x). So I can take the √9 and get 3, so the answer is 2/3sin^-1(3x)+C. But like I said, I need to show the work, and when I take (1-9x^2) for u I have no other x to account for in du. So what would my u and du be?