Find the general solution of each of the following equations:
cos x + sin x = 1
To Find: General solution.
Given: cos x + sin x = 1 cos(x -
) =
= cos
[divide on both sides and cos(x-y) = cos x cos y - sin x sin y]
Formula used: cos = cos
= 2k
, k
I
x -
= 2k
x = 2k
+
x = 2k
+
or
x = 2k
+
x = 2k
+
or x = 2k
So general solution is x = 2n +
or x = 2n
where n
I