AQA areas in Polar Graphs

I'm doing question 4 in the paper below. I've managed to get up to cii) and have done the integration but I didn't know which limits to use. I was going to do -pi to pi and then halve it but looking at the answer I'm supposed to use the values found in ci). I have no idea why. Could someone please explain, please.


http://filestore.aqa.org.uk/subjects/AQA-MFP3-W-QP-JUN07.PDF

http://filestore.aqa.org.uk/subjects/AQA-MFP3-W-MS-JUN07.PDF

As r approaches 0 what's theta doing?

In practice you're just going to use the fact that the values of theta for which r=0 give you the tangents to the curve at the origin.