06 September 2014
Rebate is in Tax Amount whereas exemption is from Total income.
Sec 87A is applicable from Fy 2013-14.
It says--
An assessee, being an individual resident in India, whose total income does not exceed five hundred thousand rupees, shall be entitled to a deduction, from the amount of income-tax (as computed before allowing the deductions under this Chapter) on his total income with which he is chargeable for any assessment year, of an amount equal to hundred per cent of such income-tax or an amount of two thousand rupees, whichever is less."