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# Solving trig equations with CAST diagrams watch

1. Attachment 537537537539Attachment 537537537539Hi please help me figure out how to do these quetions. I will put photos of the questions I'm attempting and what I have so far:

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2. (Original post by Bhansongal98)
Attachment 537537537539Attachment 537537537539Hi please help me figure out how to do these quetions. I will put photos of the questions I'm attempting and what I have so far:

Basically, for Sin Cos and Tan there are 2 values of x and then these values repeat every 360 degrees (or 2pi radians)

after finding your first value, x,

For Sin : 180 - x (or 2pi - x)
For cos : 360 - x (or pi - x)
For tan : x+180

Then add 360 to both values to find the next two values. Notice for tan you can just keep adding/removing 180.

The CAST diagram is just a way of representing this, you are always trying to find the size of the angle between the positive horizontal and your second line.

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