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# solve (1+cosx)^2=1/4 for -180<x<180 watch

1. solve the question above
2. (Original post by ramshahk)
solve the question above
1+cosx= +/-0.5
cosx= -0.5, -1.5 (-1.5 yields no solutions)
hence cosx = -0.5

You can solve the rest- should be quite straightforward from here.
3. (Original post by ramshahk)
solve the question above
Sure.

Can you in return prove that by induction on ? I'm feeling a bit lazy.
4. (Original post by OloMed)
1+cosx= +/-0.5
cosx= -0.5, -1.5 (-1.5 yields no solutions)
hence cosx = -0.5

You can solve the rest- should be quite straightforward from here.
its a quarter not half
5. (Original post by RDKGames)
Sure.

Can you in return prove that by induction on ? I'm feeling a bit lazy.
im sorry i havent learnt that yet
6. (Original post by ramshahk)
its a quarter not half
ive square rooted both sides of the equation
7. (Original post by ramshahk)
its a quarter not half
Protip: learn basic algebra and arithmetic operations before trying to solve trig equations...
8. (Original post by OloMed)
ive square rooted both sides of the equation
thaank you

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