theorem Th11: :: POLYEQ_4:11

for a, b being Real holds
( (a |^ 3) + (b |^ 3) = (a + b) * (((a ^2) - (a * b)) + (b ^2)) & (a |^ 5) + (b |^ 5) = (a + b) * (((((a |^ 4) - ((a |^ 3) * b)) + ((a |^ 2) * (b |^ 2))) - (a * (b |^ 3))) + (b |^ 4)) )