Let R denote the region bounded by the curve y=x^3 and the lines x=0 and x=4. Find the volume generated when R is rotated 360 degrees about the x axis.

The area of a circle is given by (pi)r2 and the area generated by R can be considered as an infinite number of circular areas.

Thus, we can write the area generated by R as the integral of (pi)(x3)2 between x=0 and x=4.

The (indefinate) integral is: (pi)6x5

so the area is: (pi)6(45-05)=(pi)6(1024-0)

                                      =6144(pi)

SB

Related Maths A Level answers

All answers ▸

Using the equation cos(a+b) = cos(a)cos(b) - sin(a)sin(b) or otherwise, show that cos(2x) = 2cos^2(x) - 1.


State the trigonometric identities for sin2x, cos2x and tan2x


Solve x^2=4(x-3)^2


Differentiate: tan(2x) cos(x)