
Brendan L. answered 12/01/21
Experienced Math Tutor Specializing in Trigonometry
tan^4(𝜃) − 34 tan^2(𝜃) + 225 = 0
Note that the form of the equation is similar to ax^2 + bx + c = 0
In this case tan^2(𝜃) is our "x." Therefore, we can factor this problem quite easily.
(tan^2(𝜃) - 25)(tan^2(𝜃) - 9) = 0
Both of these factors happen to be difference of squares so we can factor further.
(tan(𝜃) + 5)(tan(𝜃) - 5)(tan(𝜃) + 3)(tan(𝜃) - 3) = 0
Now set each of these factors equal to 0 to get 4 solutions
tan(𝜃) + 5 = 0 tan(𝜃) - 5 = 0 tan(𝜃) + 3 = 0 tan(𝜃) - 3 = 0
tan(𝜃) = -5 tan(𝜃) = 5 tan(𝜃) = -3 tan(𝜃) = 3
𝜃 = arctan(-5) 𝜃 = arctan(5) 𝜃 = arctan(-3) 𝜃 = arctan(3)
You can then evaluate in a calculator based on whether your answer is in degrees or radians