Suppose that 2x = 3y = 5z = 900w = A Then, ln(2x) = ln(3y) = ln(5z) = ln(900w) = ln(A) x·ln(2) = y·ln(3) = z·ln(5) = w·ln(900) = ln(A) , , , *** xyz = = *** xy = = yz = = xz = = xy + yz + xz = So 2w = 2w(xy+yz+xz) And that's what xyz was shown equal to above, marked *** Edwin
Suppose that 2x = 3y = 5z = 900w = A Then (you can also use log instead of ln, as above): log(2x) = log(3y) = log(5z) = log(900w) = log(A) x·log(2) = y·log(3) = z·log(5) = w·log(900) = log(A) , , , *** xyz = = *** xy = = yz = = xz = = xy + yz + xz = So 2w = 2w(xy+yz+xz) And that's what xyz was shown equal to above, marked *** Edwin