If tan theta = 5/6 and tan phi= 1/11 then find tan (theta + phi) hence show that (theta + phi) = (pie)/4 ?

1 Answer
May 21, 2018

Proved as described below.

Regards

Explanation:

tantheta=5/6

tanphi=1/11

tan(theta+phi)=(tantheta+tanphi)/(1-tanthetatanphi)

=(5/6+1/11)/(1-5/6xx1/11)

=((5xx11+1xx6)/(6xx11))/((6xx11-5xx1)/(1xx6xx11))

=((55+6)/66)/((66-5)/66)

=61/61=1

tan(theta+phi)=1

tan(pi/4)=1

theta+phi=pi/4