Recent content by Mathsforum100

  1. M

    Undergrad How Can the Second Derivative at a Maximum Be Zero?

    The second derivative at a maximum is either negative or zero. Can you explain how it can be zero? There can't be a 'plateau' at the maximum or it would not be a point. I cannot imagine graphically how the second derivative at a maximum can be zero. Before the maximum, the gradient is...
  2. M

    High School Not Complex Numbers: Are There Any Other Options?

    Are there any numbers in mathematics that are not complex numbers?