Prove the following identity algebraically?
I know that the LHS can be expanded to 2sintcost. I'm not sure how to solve this problem
I know that the LHS can be expanded to 2sintcost. I'm not sure how to solve this problem
1 Answer
Nov 5, 2017
Explanation:
#"left hand side "=sin2t=2sintcost"#
#"right hand side"#
#=(2tant)/(1+tan^2t)#
#•color(white)(x)1+tan^2t=sec^2tlarrcolor(blue)"Pythagorean identity"#
#=(2tant)/(sec^2t)#
#•color(white)(x)sect=1/cost" and "tant=sint/cost#
#=(2tant)/(1/cos^2t)=2xxsint/costxxcos^2t=2sintcost#
#rArr"LHS "=" RHS"rArr"proved"#