How Do You Solve sinx(sin x + 1) = 0 for All Solutions?

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SUMMARY

The equation sinx(sin x + 1) = 0 can be solved by setting each factor to zero, yielding two cases: sin x = 0 and sin x = -1. The solutions for sin x = 0 occur at x = nπ, where n is any integer. For sin x = -1, the solution is x = -90° + 360°k, where k is any integer. Understanding the periodic nature of the sine function is crucial for finding all solutions.

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I'm having trouble starting off with these equations:

sinx(sin x + 1) = 0

I can solve sin x + 1 =
Sin x = -1
x = -90

but then I don't know how to find all the solutions. Can someone please explain it to me. Thanks.
 
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if h(x) = f(x)g(x), then h(x) = 0 if either f(x) = 0 or g(x) = 0, or f(x) = g(x) = 0, i.e. they have a common root.

Based on sinx (sin x + 1) = 0

one can have two possibilities: sin x = 0 and sin x = -1.

Consider if sin x = a, then x = sin-1 (a), and remember that sin is a periodic function, i.e. sin x = sin (pi - x) and sin x = sin (x + 2pi).
 

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