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]
So sin x = 0 or cos x = 0
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-1)
where n
I