I am trying to workout this problem (See attached picture) but the hint is confusing me more than helping. I'm not sure how to progress.

(3) (8 points) Show that r- +1 - cost y lim = 1. (z.1/) - (0.0) I2+ yz Hint: First, show that 1 - cost y lim = 1. This allows you to write 1 - cosy = c(y) . y' with c(y) - 1 as y - 0. Substitute and rewrite into polar coordinates