6.2 volume Flashcards
1
Q
when and how to use disk method
A
y(x) given revolving around x axis aka y=something
x(y) given revolving around y axis aka x=something
V=π∫[r(x)]^2dx
2
Q
when and how to use washer method
A
same as disk, outer disk-inner disk
y(x) given around y=something
x(y) given around x=something
V=π∫([R(x)]^2–[r(x)]^2)dx
3
Q
how to do volume of solids w known cross sections
A
With known area function A(x)
V=∫A(x)dx or for y
4
Q
when and how to do shell method
A
representative rectangle of shell is parallel to axis of revolution
V=2π∫r(y)h(y)dy revolving around y=something and switch for x