could someone please try and solve this? and explanation would be greatly appreciated too ! this was one of the homework questions, but i didnt really understand. the teacher explained it again to the class partly, but didnt understand a part of it so we didnt continue... maybe one of you guys could do it? its grade 11 (IB) math , and Its derivative optimization of trig functions i uploaded the question (thers a schema with the question too) http://photos-h.ak.fbcdn.net/hphotos-ak-snc3/hs145.snc3/17245_418921415214_614755214_10740817_1385551_n.jpg [Broken] reply asap ! :P thankss !!