Test Academy | Two forces, with equal magnitude F, act on a body and the magnitude of the resultant force is F/3 . The angle between the two forces is cos⁻¹(-17/18), cos⁻¹(-1/3), cos⁻¹(2/3), cos⁻¹(8/9)

Question

Two forces, with equal magnitude F, act on a body and the magnitude of the resultant force is F/3 . The angle between the two forces is

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