12 grade maths others
The exact value of cos 3π/4 is
- A: -1
- B: -√3/2
- C: -√2/2
- D: -1/2
The exact value of cos 3π/4 is
- A: -1
- B: -√3/2
- C: -√2/2
- D: -1/2
1 Answer
Askiitians Tutor Team
Approved Tutor Answer9 Months agoThe value of cos(3π/4) can be determined by understanding its position on the unit circle. The angle 3π/4 radians is located in the second quadrant, where the cosine values are negative.
Finding the Cosine Value
To find cos(3π/4), we can use the reference angle. The reference angle for 3π/4 is π/4, which has a cosine value of √2/2. Since 3π/4 is in the second quadrant, the cosine will be negative.
Calculation
- cos(π/4) = √2/2
- Therefore, cos(3π/4) = -√2/2
Thus, the exact value of cos(3π/4) is -√2/2. This corresponds to option C.
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