Answer: b. [tex] \frac{ \pi }{4} or \frac{5 \pi }{4} [/tex]
Explanation: Before we begin, remember that: tan α = [tex] \frac{sin \alpha }{cos \alpha } [/tex]
Now for the given, we have: cos θ - tan θ * cos θ = 0 cos θ - [tex] \frac{sin (theta)}{cos (theta)} [/tex] * cos θ = 0 cos θ - sin θ = 0cos θ = sin θ Now, divide both sides by cos θ, we get: 1 = tan θ
Following the ASTC rule, we know that the tan function is positive in the first and third quadrants. This means that: either θ = [tex] \frac{ \pi }{4} [/tex]
