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1.Prove : (i)cosec A+1/cosec A-1 = (sec A + tan A)2 (ii)sin A/sin(90-A)+cos A/cos(90-A) = sec A cosec A 2.Find x, if: sin47 sec43 + cos43 cosec 47-x cos2 45 = 0 3.If A + B =90;prove that: (i)cos A/sin B + sin A/cos B = 2 (ii)cos A sin B + sin A cos B = 1 4.Mr.Sharma invests Rs.2,40,000 for 2 years at 10% compounded annually.On the interest he earns,income tax at the rate of 20% is deducted at the end of each year.How much money will Mr,Sharma receive at the end of two years?