chem / hdpe.outon commit add methods notes on solving trig equations (1cb56c1)
   1\BOOKMARK [1][-]{section.1}{Invention and Manufacture}{}% 1
   2\BOOKMARK [1][-]{section.2}{Structure}{}% 2
   3\BOOKMARK [1][-]{section.3}{Uses}{}% 3
   4\BOOKMARK [1][-]{section.4}{Health and environmental issues}{}% 4