**Tangent** of an acute angle is the ratio between the opposite collet measurement and the adjacent collet measurement at that angle.

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*Comments:*

1. The tangent of an acute angle can be defined as the ratio of the sine of this angle to its cosine.

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2. The tangent of an acute angle is a positive real number.

3. The sine and cosine of an acute angle are always positive real numbers less than 1, since any collet is always smaller than the hypotenuse.

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