- #1

- 50

- 4

- Homework Statement
- Why are the limits of integration swapped in the following equation without introducing a minus sign?

- Relevant Equations
- ##\int_0^1\sqrt{\frac{1}{x}-1}dx##

Initially '0' is the upper limit and ##a = \frac{Ze^2}{E}## is the lower limit. With change of variable ##x = \frac{Er}{Ze^2}##, for ##r=0##, ##x=0##, and for ##r=\frac{Ze^2}{E}##, ##x=1##, so 1 should be the lower limit. However, he takes 1 as the upper limit, and without a minus sign. Why is that?

(from Quantum Mechanics, Nouredine Zettili)