Question 998480
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please help me with the question: sin x=1 - cos x 
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Hey,  this is not a question.  It is an equation.

If you want to solve it,  say  "Please help me solve this equation".


OK,  let's solve it.


sin(x) = 1 - cos(x).


In the left side,  replace  sin(x) = {{{sqrt(1-cos^2(x))}}} to get the equation for one uniform unknown  cos(x):


{{{sqrt(1-cos^2(x))}}} = {{{1 - cos(x)}}},   ---> square both sides --->


{{{1 - cos^2(x)}}} = {{{1 - 2*cos(x) + cos^2(x)}}},


{{{2*cos^2(x) - 2*cos(x)}}} = {{{0}}},


{{{2*cos(x)}}}.{{{(cos(x)-1)}}} = {{{0}}},


a)  cos(x) = 0   ----->  x = {{{pi/2 + k*pi}}},  k = 0, +/-1, +/-2, . . . 


b)  cos(x) = 1 ----->   x = {{{k*pi}}},  k = 0, +/-1, +/-2, . . .