tan-1( 2x/1-x^2) + cot-1 1-x^2/2x^2) = pie/3

plz proove

tan^-1(2x/(1-x²)=2tan^-1x

cot^-1((1-x²)/2x²)=tan^-1(2x²/(1-x²))

use the formula: tan^-1a + tan^-1b =tan^-1((a+b)/(1-ab))

now i have only 20 days to my board exams.... suggest some tricks and time management for phy. and chem..

regards