Given that cosine theta = -1/2, and theta is obtuse, find:

a) sine theta

b) sine 2(theta)

c) tangent theta

d) sine 4(theta)

Answers:

a) 0.86

b) -0.86

c) -1.73

d) 0.86

Step-by-step explanation:

We are told . So, we first have to find the value of which is an obtuse angle (an angle greater than and smaller than ):

Now that we know the value of the angle , let's begin with the answers:

a)

b)

c)

d)

12

step-by-step explanation:

a triangle's   full angle is 180 degrees so 180 - 156 = 24. 24/2=12