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...
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)...