% Ladder in the Mine
a = 123*2*pi/360
L = inline('9/sin(pi-a-c)+7/sin(c)')
L = inline('9/sin(pi-2.1468-c)+7/sin(c)')
fplot(L,[0.4,0.5]); grid on
fminbnd(L,0.4,0.5)
L(ans)
min_c = fminbnd(L,0.4,0.5)
L(min_c)