Question

tan a=1/2, tan b=1/3 find cos 2a without using answers given below

Answer 1

Answer:

if we see the formula of tan: p/b

hence if we assume a triangle ABC,

then, hypotenuse will be = 3

  base = 1 or 2

perpendicular = 2 or 1

so, 2 cos a = B/H

                  = 1/3 or 2/3

Step-by-step explanation: