If a cost of a function is C(x) = (49 ln x) / (28-3x), find the marginal cost when x = 7

Answer 1

marginal cost is
dC/dx = 49(-3x+3lnx+28)/(28-3x)^2
so at x=7, dC/dx = (7 + 3 ln7)/49

Answer 2

a ship sails 6 kg on a bearing 160• and then a further 10 kg on a bearing 240 as shown how far this ship from starting this point