theorem FRds3: :: ZMODUL04:29

for V being LeftMod of INT.Ring
for W1, W2 being free Subspace of V
for I1 being Basis of W1
for I2 being Basis of W2
for I being Subset of V st V is_the_direct_sum_of W1,W2 & I = I1 \/ I2 holds
I is linearly-independent