# Math 2

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• Yes! Also, you made an error when solving one of your solutions.
• Huh? How?
• When you were simplifying sinx=-1/2, you automatically assumed that one of the solutions was 30.
• Since -1/2 is negative, 30 is only the reference angle. You will need to choose the correct quadrants and use 30 to find the two solutions.
• These are all the errors you made. If you fix it up, you should get the answer right!
• Im still a little bit lost. Can you explain how to answer the question step-by-step?
• Firstly, you will need to simplify the equation. You use a trigonometric identity and convert Cos2x into 1-Sin2x.
• The two individuals went to the woman's house, so she can explain how to solve the question.
• Then, you will let a represent Sinx and simplify the equation. You should get (-3a+1)(2a+1)=0.
• You will be able to get two equations from this: Sinx=1/3 and Sinx=-1/2. For SInx=1/3, the reference angle is 19.5°.
•  You use the CAST rule to see that this equation is in the 1st and 2nd quadrants. This means that the other solution is 160.5°.
• For Sinx=-1/2, the reference angle is 30°. However, this is not one of the solutions because the CAST rule shows that it has to be in quadrant 3 and 4.
• This means that the solutions are 210° and 330°.
• OH MY GOD! I GET IT! THANK YOU SO MUCH!
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