A fellow classmate mistakenly thinks that cos(45°) = 0.5 and sin(45°) = 0.5. Explain why he might think this and why it is not possible.?

2016-09-28 4:00 am

回答 (3)

2016-09-28 4:10 am
✔ 最佳答案
Pythagorean Identity: cos²θ + sin²θ = 1

cos²(45°) + sin²(45°) = ¼
2016-09-28 4:06 am
Given a 45/45/90 the hypo is sqrt(2), and he might have written 1/2 instead of 1/sqrt(2)

:)
2016-09-28 4:11 am
45°/90°=.5 does not explain the values of sin(45°) and cos(45°). sine and cosine are not linear functions. Moreover, refer to the sides of a isosceles right triangle to see what both values must be, 1/√2.


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