2 cos x plus 1 cos x plus -1 equals 0?

To solve the equation 2cos(x) + cos(x) - 1 = 0, we first combine like terms to get 3cos(x) - 1 = 0. Then, we isolate the cosine term by adding 1 to both sides to get 3cos(x) = 1. Finally, we divide by 3 to solve for cos(x), which gives cos(x) = 1/3. Therefore, x = arccos(1/3) or approximately 70.53 degrees.