Could someone explain what logic I need to use to complete the following sudoku (this is as far as I get, then I don't know what techniques to use!):
1 9 5 - 6 8 4 - (2/3) (2/3) 7
6 7 2 - 5 9 3 - 1 8 4
3 4 8 - (1/2) 7 (1/2) - 6 5 9
4 6 7 - (8/9) 2 (8/9) - 5 1 3
5 2 1 - 7 3 6 - (4/9) (4/9) 8
9 8 3 - 4 1 5 - 7 6 2
(2/8) (1/3) 9 - (1/2/3/8) 5 (1/2/7/8) - (2/3/4/8) (2/3/4/7) 6
(2/8) 5 6 - (2/3/8/9) 4 (2/7/8/9) - (2/3/8/9) (2/3/7) 1
7 (1/3) 4 - (1/2/3/8/9) 6 (1/2/8/9) - (2/3/8/9) (2/3/9) 5
I have left spaces between each component and have put options for the missing values in brackets -trial and error seems the only option, but there must be a way (please help!)
(apologies if this is not clear, and if you have to write this out again to make it clearer)