Recent content by chung963

  1. C

    Dimensions of cone with smallest volume that can hold a cylinder

    Homework Statement A cylinder of height 45mm and radius 12mm is placed inside a circular cone. What are the dimensions of the cone with the smallest volume to enclose this cylinder Homework Equations v=1/3(pi)r^2h v=(pi)r^2h SA=2(pi)rh The Attempt at a Solution I substuted values...
  2. C

    Differentiating a trig function to the power of 2

    Homework Statement I'm doing a optimisation question and I get to a point where I have to verify a maximum using a double derivative and I need to differentiate -5sin^2(x) Homework Equations -5sin^2(x) The Attempt at a Solution -10cos(x)sin(x) I am not sure if the answer is positive...
  3. C

    Double derivative of a quotient

    Find d^2y/dx^2 when dy/dx = (3x^2 - 24x - 45) ÷ 2y i tried by (6x-24) ÷ 2y. Unsure what to do about the y on the denominator.