Sine angles with a difference of π
sin(π + x) = -sinx
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Question 1
.What is the value of sin210° ?
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Question 1 - Answer
sin210° = sin(180° + 30°) = -sin30° = -1/2
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Question 2
What is the value of sin225° ?
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Question 2 - Answer
sin225° = sin(180° + 45°) = -sin45° = -1/√2 or -√2/2
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Question 3
What is the value of sin240° ?
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Question 3 - Answer
sin240° = sin(180° + 60°) = -sin60° = -√3/2
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