# Trig Equation

1. Jun 5, 2009

### Imperil

a) Use the special triangles and the CAST rule to solve the equation 2sinx + $$\sqrt{3}$$ = 0 for the domain interval 0 $$\leq$$ x $$\geq$$ 360.

b) What feature of the graph, in the form y = asinx + b, would show the solutions?

a) sinx = -$$\sqrt{3}$$/2
x = -60 degrees

180 + 60 = 240 degrees
360 - 60 = 300 degrees

b) Can anybody give me a clue as to what this is asking? I have absolutely no idea :(

2. Jun 5, 2009

### Staff: Mentor

For b, think about where the graph of y = 2sinx + sqrt(3) crosses the x-axis. I think that's what the problem is getting at.

3. Jun 5, 2009

### Imperil

This is what I was thinking of as the graph will cross x at 4Pi/3 and 5Pi/3, so I was thinking that the feature to show the solution would be the x-intercepts.

Is this correct? I originally thought this but then was confused by the words "feature of the graph"

4. Jun 5, 2009

### Staff: Mentor

An x-intercept is a feature of a graph. Again, I think this is what the question is getting at.