Recent content by gracie189

thankyou =) that makes sense.. and yes there was a 4pi in there come to think of it i must hav accidentaly left it out.. ..now i'll go do it agen n make sure i can do it.. i hate not being able to finish questions, or find teh right answer... it drives me crazy... and yeh... i dnt get this...

yeah but isnt the shell method for finding volumes..? this was only the first half of the question, and you were supposed to find the area of the circular.. well i suppose call it a disc or a washer or whatever.. i still kinda havent got the grasp of the method of shells completely.. we only did...

Question - the region bounded by the curve y = (x-1)(3-x) and the x axis is rotated about the line x = 3 to form a solid. When the region is rotated, horizontal line segment l at height y sweeps out an annulus. Show that the area of the annulus A=square root(1-y) (sorry i dont kno how t put th...