If the derivatives transactions are frequent in nature and unrelated to the shareholding or the share transactions, generally such derivatives transactions would be regarded as having been carried out for earning short-term profits and income from such transactions would, therefore, be taxable as business income.
But where the derivatives transactions are closely linked with share investments, say, hedging transactions to safeguard against fall in share prices of existing share investments, one can’t say that the derivatives transactions are in the nature of a business. The issue then is: whether income from these transactions would be taxed as capital gains or as income from other sources? While it is possible to take a view that the income from such derivatives transactions is taxable as capital gains, it is possibly a safer approach to treat such income as income from other sources. In any case, the rate of tax for both these types of income is the same (your slab rate) since the capital gains are short-term capital gains on securities other than equity shares or units. Therefore, other than for the purpose of setting off of loss, there is no difference if such income is taxed as capital gains or as income from other sources.