When is cosα a x component or y component in a problem?

Thread starter pillar
Start date Sep 20, 2009
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Cosα is used for the x-component when the angle α is measured from the x-axis, as it represents the horizontal coordinate on the unit circle. Conversely, when α is measured from the y-axis, cosα represents the y-component. Understanding the reference axis is crucial for determining the correct application of cosα in problems. An example clarifies that the orientation of the angle dictates which component is being calculated. Proper identification of the reference axis is essential for accurate vector resolution.

Sep 20, 2009

pillar

How when do you know when to use cosα in the x component or y component?

I thought you only use cosα on the x component since it's the x coordinate on the unit circle.

Can somebody give me an example, I would appreciate it.

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Sep 20, 2009

Redbelly98

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If α is the angle taken from the x-axis or horizontal, then cosα is the x-component.

If α is taken from the y-axis or vertical, then cosα is the y-component.

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