Recent content by s.perkins

Homework Statement let Bn be a ball in Rn with radius r. ∂Bn is the boundary. Use divergence theorem to show that: V(Bn(r)) = (r/n) * A (∂Bn(r)) where V(Bn) is volume and A(∂Bn) is surface area. Homework Equations consider the function: u = x1 ^2 + x2 ^2 +...+ xn ^2 The...

Homework Statement The question is as follows: if |m| = 4, |n| = 3, and the angle θ between m and n is 5pi/6, find the norm of the vector m + 2n. Homework Equations Im attempting to use the equation : cosθ = (m * n)/(|m||n|) The Attempt at a Solution I determined using the...

Sorry fixed the typo. I did include the 1/2, when its squared you get a 1/4 in front.

Homework Statement Show that cosh^2(x) = (cosh(2x) - 1)/2 Homework Equations cosh(x) = (e^x + e^-x)/2 The Attempt at a Solution I have attempted this multiple times and get the same results every time. Squaring cosh(x) I get 1/4(e^2x + e^-2x +2), which is i believe 1/4(cosh(2x) +2)...