Given that cos theta = 1/sqrt2, and -180degrees =< theta =< 0degrees, determine possible coordinates for point P on the terminal arm of theta.
Help would be really appreciated!
Given that cos theta = 1/sqrt2, determine possible coordinates.?
2021-02-21 1:53 pm
回答 (3)
2021-02-21 4:40 pm
✔ 最佳答案
For cosθ > 0 and -180° ≤ θ ≤ 0°,θ is in the fourth quadrant, i.e. sinθ < 0
sin²θ + cos²θ = 1
sin²θ + (1/√2)² = 1
sin²θ = 1/√2
Hence, sinθ = -1/√2 for sinθ < 0
Refer to the diagram below:
The coordinates of P
= P(|OP|cosθ, |OP|sinθ)
= P(|OP|/√2, -|OP|/√2)
2021-02-21 2:33 pm
If P is (x, y), then either:
1. x = y, with x and y both positive
2. x = -y, with x positive and y negative
1. x = y, with x and y both positive
2. x = -y, with x positive and y negative
2021-02-21 1:54 pm
Sorry dude, if you're anon you're not going to receive answers.
收錄日期: 2021-04-24 08:48:12
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