We need to find the original function u corresponding to the transformed
We do not really know what 
is, just that it transforms back
to g. However, we can find the other part of 
in the
tables.
How does times this function transform back? The product of
two functions, say 
, does not transform back
to f(t)g(t). The convolution theorem Table 6.3 # 7 is needed:
