# find all solutions in the interval of [0, and 2pi)

• April 27th 2009, 12:43 PM
jumpman23
find all solutions in the interval of [0, and 2pi)
A.) 3sec^2(x/2)-4sec(x/2)-4=0

B.) tan^2x = (-3/2)-secx
• April 27th 2009, 12:47 PM
Jameson
Quote:

Originally Posted by jumpman23
A.) 3sec^2(x/2)-4sec(x/2)-4=0

B.) tan^2x = (-3/2)-secx

For A, use a nice little trick by making the substitution $u=\sec{\left(\frac{x}{2}\right)}$. Notice now that you have a quadratic equation for u. So solve it then back substitute and solve.