Question

tan a=2/5 tan b=3/7 find(a+b)

Answer 1

tan(a+b)=(tana+tanb)/(1-tana*tanb)
=(2/5+3/7)/(1-2/5*3/7)
or tan(a+b) =29/29
hence tan (a+b)=1=tan45°
a+b=45°

Answer 2

Answer:

if tan a equals to 2 by 5 and 10 b equals to 3 by 7 then prove that a + b = 2 pi by 4