theorem RI2: :: NEWTON03:2

for k, n being Nat
for a1, b1 being Complex holds (a1 |^ (n + k)) - (b1 |^ (n + k)) = ((a1 |^ n) * ((a1 |^ k) - (b1 |^ k))) + ((b1 |^ k) * ((a1 |^ n) - (b1 |^ n)))