Steps to Find the Value of Cos 90 Degrees | CBSE Maths Exam Notes

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There are two methods to find the value of cos 90 degrees are:

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Cos 90° in Terms of Trigonometric Functions:

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Note:

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We can use trigonometric identities to represent cos 90°.

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Cos 90 Degrees Using Unit Circle:

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Rotate ‘r’ anticlockwise to form 90° angle with the positive x-axis.

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The cos of 90 degrees equals the x-coordinate(0) of the point of intersection (0, 1) of unit circle and r.

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Hence the value of cos 90° = x = 0

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