I don't understand what they have done in the mark scheme where I have put a red box around the part that I don't understand. Please help. Thanks in advance.
They are using a standard result, The center of mass of a uniform solid right circular cone is distance from the base (where h is the height of it.)
I attached the formula you will be given in your M3 exam if your interested in it.
...And what did they do to get ? What rule is it that says external angle equals that of the internal?
the tangent is just a given, they didn't work it out they defined it to make working out the height a bit more interesting.
Originally Posted by Air