
Bradford T. answered 09/06/21
Retired Engineer / Upper level math instructor
f(y) = y2 g(y) = 1-y2
Setting f(y) = g(y)
y2=1-y2 --> y = ±√1/2 --> a = -√1/2 b= √1/2
Volume, V = π∫ab|(f(y)-d)2-(g(y)-d)2|dy where d = 3 in this case
V = π∫ab|(y2-3)2-(-y2-2)2| dy = π∫ab|-10y2+5|dy = π(-10y3/3 +5y)|ab = π(-5√2/3+5√2) = (10/3)√2π