Question

Is this problem http://imgur.com/58njB integrating improperly? Shouldn't it be positive 2 not negative. Also isn't he subtracting the wrong way around?

Answer 1

\[u=3-x\]\[du=-dx\]\[-du=dx\]\[-\int\limits u^{-1/2}du\]\[-2u^{1/2}|_{0}^{t}\]\[-2\sqrt {3-x}|_{0}^{t}\]\[-2\sqrt {3-t}+2\sqrt{3}\]It is correct