Ok, I know the Pythagorean identities but can't seem to solve these two question.
Evaluate. Give exact anwser.
sin² π/6 - tan² π/4 + cos² π/6
so all I can do on this question so far is use the identity sin x + cos x= 1 to get to
1 - tan² π/4
then I am lost.
The next question I have no idea what to do.
Solve the following equation
1 - 2 cos²Θ = -sinΘ, 0<Θ<2π
i got to the point sinΘ=1/2 or sinΘ=-1. Now do I reject -1 because because 0<Θ<2π or am I missing something? Also, how do I get rid of the sin?
I realize this stuff is elementary but I feel that my teacher gave an insufficient explanation for the trig unit.
Please show all your work if you need more help.
Here is all my work for the second question. Still can't find the answer... maybe math isn't my forte