Page 52 - Math SL HB Sem 2

= l"l;1rtl'a*

a) Volume of a solid of revolution:
i) revolve about the x-axis

If the plane figure bounded bY v
the curve y=f(x), the x'aiis, v
and the lines at x=a ard x=b, x)
rotates through a corqPiete
revolution (360P) about the x-
axis, it will generate a solid
symmetrical about OX- x=a x=b
The volume of the solid
b
F a,
generated, V = JfiY aa

Example 32: Find the volume of the solid that results by revolving the region enclosed by the

lines x + y= 5,y:Oandx =0 through 2 [l about x axis' [ans: !1r]
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