Solve the equation 2sec^2theta+3tantheta=1?

1 Answer
Jun 12, 2017

theta=2.678 or 2.3562 radians

Explanation:

As sec^2theta=1+tan^2theta

2sec^2theta+3tantheta=1 can be written as

2+2tan^2theta+3tantheta=1

or 2tan^theta+3tantheta+1=0

i.e. (2tantheta+1)(tantheta+1)=0

Hence either tantheta=-1/2=tan(pi-0.4636)=tan2.678 (in radians)

or tantheta=-1=tan((3pi)/4)=tan2.3562 (in radians)

These are results in [0,pi]