X=tan(a+b)+tan(a-b),y=tan(a+b)tan(a-b) then x equals to and y equals to

Convert Tan to sin and Cos  For calculating x = tan(a+b) + tan (a-b) take sin/cos and then take the LCM and you will see sin(a+b)cos(a-b) +cos(a+b) sin(a-b) in Numerator which is sin 2a formulae and in denominator you can use product to sum formulae.  For Getting y write Tan as Sin/cos  and then convert product of sin to cos-cos and denominator of cos cos to cos + cos