Ex.Ex.Tax

hi dear as know ex. ex. tax is a provision under tax where exmepted incomes under chapter VI are combined together & they combinelly exmepted but if any other income drived from that expted incomes then that income is taxable in hands of assessee . eg: if assessee purchase IVP & NSE it is expted form tax but interest recieved is taxable in hands of assessee that is expt-expt-tax