Find the solutions of the given equation in the indicated interval.
20 (cos(x))^2 + cos(x) − 1 = 0, [0, π]

Question

Find the solutions of the given equation in the indicated interval. 
20 (cos(x))^2 + cos(x) − 1 = 0,      [0, π]

anonymous · Answer

what is that 20 doing there?

anonymous · Answer

its in front of cosx^2

anonymous · Answer

yeah that one

anonymous · Answer

yeah its 20 in front of cosx^2...

anonymous · Answer

anonymous · Answer

i am going to make a guess that is it is supposed to be a 2

anonymous · Answer

$$2(\cos(x))^2+\cos(x)-1=0$$ that you can solve

anonymous · Answer

that one factors as 
$$(2\cos(x)-1)(\cos(x)+1)=0$$ set each factor equal to zero, solve for $x$