Your capital gains will be taxed at 0% or 15% or 20% only if they are long term capital gains. Now assuming that they are long term capital gains, your $50,000 in income will be taxes at its ordinary income rate. The tax calculated on the return is $1,000,000 at its long term rate plus $50,000 at the ordinary income tax rate. So say you fall in the 15% bracket for long term gain tax and 12% in the ordinary income tax bracket, your tax will be $150,000 ($1,000,000 at 15%) plus $6,000 ($50,000 at 12%) = $156,000.
Now if your capital gains of $1,000,000 is not a long term capital gain but instead a short term capital gain, then ordinary income tax will be calculated on the total $1,050,000 at the regular income tax rates.
