(* CALCULUS 265 Honors Fall Semester 2000 8:00 to 8:50 MTTF Carver 0002 Instructor: Hentzel Office: 432 Carver Office Hours: 9:00-10:00 MTTF E-mail hentzel@iastate.edu phone 294-8141 Website http://www.math.iastate.edu/hentzel/honors.265 <##### NEW ADDRESS #### Tuesday, September 12: Section 13.3 p930:9 p931:11,16,19 p939:7 p940:9,19,20 A pile of sand is a cone with altitude six feet and radius of base 6 feet. Unfortunately it extends one foot across the lot line. The neighbor complains, and the contractor agrees that the neighbor can have the sand that is on the neighbor's property. They come to you, a college educated person. Tell them how much sand should belong to the neighbor. Use Mathematica to evaluate the volume in four ways. *) f[x_,y_] := 6 - Sqrt[x^2 + y^2]; (* Integrate dy dx *) (* Integrate dx dy *) (* Integrate dr dt *) (* Integrate dt dr *) (* Which of the four is this ? *) h = Integrate[ f[r Cos[t], r Sin[t]] r,{r,5 Sec[t],6}] Integrate[h,{t,-ArcCos[5/6],+ArcCos[5/6]}]; (* Which of the four is this ? *) h = Integrate[ f[r Cos[t], r Sin[t]] r,{t,-ArcCos[5/r],+ArcCos[5/r]}]; Integrate[h,{r,5,6}]; (* Which of the four is this ? *) h = Integrate[f[x,y],{x,-Sqrt[36-y^2],+Sqrt[36-y^2]}]; Integrate[h,{y,5,6}] (* Which of the four is this ? *) h = Integrate[f[x,y],{y,5,Sqrt[36-x^2]}]; Integrate[h,{x,-Sqrt[36-5^2],+Sqrt[36-5^2]}];