Help on this one too?
"Find 'all' of the solutions for the following equation: 2cosx - 1 = 0"

Question

Help on this one too?
"Find 'all' of the solutions for the following equation: 2cosx - 1 = 0"

shamim · Answer

Cos x=1/2
Right?

anonymous · Answer

sure?
I honestly don't know.

yamyam70 · Answer

$$x = \cos^-  1/2$$

yamyam70 · Answer

to check this substitute that value with x 

$$2 \cos ( \cos^- 1/2) -1 = 0 $$

yamyam70 · Answer

if the final answer is  0 = 0 , 
then it is a solution

anonymous · Answer

ok, so if I'm finding all solutions, would the only solution be 0?

shamim · Answer

2cos x=1
Right?

yamyam70 · Answer

It depends on what your given is equated to 

in this case it is equated to 0 , 

so to know if it is a solution substitute values and put them in calculator ,

if the result is 0 in your calculator and the given is equated to zero. It is a solution


This also applies to whatever your given is equated to., for example if it is equated to 1 
result should be 1 , and 1 is equal to 1, 1=1 therefore it is a solution

michele_laino · Answer

@babygabe97  please note that:
|dw:1418570659969:dw|

anonymous · Answer

ok, I see now.

shamim · Answer

Feel free to ask if u hv any confusion