| 摘要 |
A planar member 21, is pivotally assembled to a transparent planar member 22, at pivot point 23. On the planar member 21, are the calibrated circle 24, the cosine/secant scale 25, and the sine/cosecant scale 26. On the transparent member 22, are the sine/cosine cursor circle 27, the tangent/cotangent scale 28, and the arrow head 29. For any relative position of the two members, the arrow head 29, points to an angle. Each of the six trigonometric functions of that angle is read where the appropriate scale is intersected by another line. FIG. 2, shows the device set at 150 degrees as an example. The sine and the cosine of 150 degrees are read at intersections 33 and 34 respectively. The secant and the tangent at intersection 31. The cosecant and cotangent at 32. The sign of any cotangent reading needs to be reversed.
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