Question Detail

MTH 101 MTH 101 Past Questions Objective Question
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Question

Evaluate \( \sin(-225^\circ) \) without the use of e-calculator or figures tables.
Options
A \( \frac{\sqrt{2}}{2} \)
Correct Answer
B \( \frac{\sqrt{3}}{2} \)
C \( \sqrt{3} \)
D \( \frac{\sqrt{3}}{3} \)
Correct Answer

Option A is the correct answer.

Detailed Explanation

sin(-225°) = -sin(225°) (since sin is odd). 225° is in the third quadrant (180° + 45°), where sin is negative. sin(225°) = -√2/2. So -sin(225°) = -(-√2/2) = √2/2.

Hint

Use the property sin(-θ) = -sinθ. Then find the reference angle for 225°.

Question Info

Course: MTH 101
Topic: MTH 101 Past Questions
Type: Objective
Difficulty: Not specified
Question 525 of 696
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