Let \(S^2=\{(x,y,z)\in \mathbb {R}^3:x^2+y^2+z^2=1\}\) be the unit sphere. Let \[ \omega = \begin {cases} \dfrac {dy\wedge dz}{x}, & \text {if } x\ne 0;\\[1ex] \dfrac {dz\wedge dx}{y}, & \text {if } y\ne 0;\\[1ex] \dfrac {dx\wedge dy}{z}, & \text {if } z\ne 0. \end {cases} \]
- Show that \(\omega \) is a well defined two form on \(S^2\)
- Find \(\displaystyle \int _{S^2}\omega \).
- Is \(\omega \) exact? Why?