Question

Cos 2x + 3 = 4 can some one help me with finding all solutions

Answer 1

x=0 or x=pi / x=πn

Explanation:

cos2x + 3 = 4

subtract 3 from both sides

cos2x = 1

take the inverse cos/arccos of both sides

arccos(cos2x) = arccos(1)

2x=0 or 2x=2pi

divide both sides by 2

x=0 or x=pi

beyond (0,2pi) for every possible answer you should do x=(pi)n since any multiple of pi gives you the same answer