MATL, 12 11 bytes
Saved a byte thanks to Luis. I keep forgetting the &
is a shortcut for duplicating and transposing.
10:&*11\10\
10:&*11\10\
Using @Martin's algorithm: x*y % 11 % 10
Explanation:
10 % Pust 10 to the stack. Stack: 1
: % 1-based range. Stack: [1 2 3 ... 10]
& % Duplicate range. Stack: [1 2 3 ... 10],[1 2 3 ... 10]
% Transpose last range. Stack [1 2 3 ... 10],[1;2;3 ...10]
* % Multiply with broadcasting. Stack: [1 2 3 ...;2 4 6...] (10-by-10 array)
11 % Push 11 to the stack. Stack [1 2 3 ...;2 4 6 ...], 11
\ % Modulus.
10 % Push 10 to the stack.
\ % Modulus
% Implicit display
Same bytecount:
10t:&*11\w\