1. Set up the equation for the volume of the cylinder
Let the height of the cylinder be h.
Volume V=πr2h
(6+23)π=π(1+3)2h
2. Expand the square of the radius and simplify the equation
(6+23)=(1+23+3)h
6+23=(4+23)h
h=4+236+23
h=2+33+3
3. Rationalise the denominator to find the height in the required form
h=2+33+3×2−32−3
h=4−36−33+23−3
h=13−3
h=3−3