Whether the income from other sources under income tax is taxable under GST?

No , as income taxable in gst is shown as business income and ifos income is only taxable in income tax

No it is not taxable in gst ?
but what is your other sources

Most common other source incomes like interest and dividend would not attract GST, but it mainly depends on the nature of income.

GST's definition of business not only coverd the principal business activity, but also includes all supplies incidental to business. Due to this wider scope, there can be income that is classified as "income from other source" under income tax but since they are activities incidental to the business, they will be considered supply and there GST will be levied.

In short, some of the other source income can be taxable. It depends solely on the nature of income.

One is direct tax and another is indirect tax.

If , other sources not forming part of your business income , thats not taxable!

Income from other sources is commonly used in Income tax parlance.

There are various sources:
1.dividends
2.income from crossword puzzle
3.contributions received by an employer
4.rent from plant and machinery
5. any sum received from keyman insurance policy.

therr are others....