Question

Solve the following for θ, in radians, where 0≤θ<2π.

5cos2(θ)−8cos(θ)+2=0
Select all that apply:

2.85
5.03
1.26
1.37
1.86
0.61

Answer 1

Answer:5.03

1.26 are correct

Step-by-step explanation:We can solve this quadratic equation in cos(θ) by using the substitution u = cos(θ):

5u^2 - 8u + 2 = 0

We can use the quadratic formula to solve for u:

u = (-b ± sqrt(b^2 - 4ac)) / 2a

where a = 5, b = -8, and c = 2. Substituting these values, we get:

u = (8 ± sqrt(64 - 40)) / 10

u = (8 ± 2sqrt(6)) / 10

Therefore, either: