1. The problem is to understand the terms 'cahsign' which likely refers to 'cosine, adjacent, hypotenuse sign,' a mnemonic for trigonometric ratios. 2. The cosine of an angle in a right triangle is defined as the ratio of the length of the adjacent side to the length of the hypotenuse. 3. This is written as $$\cos(\theta) = \frac{\text{adjacent}}{\text{hypotenuse}}$$. 4. To use this in a problem, identify the angle $\theta$, then measure or know the lengths of the adjacent side and hypotenuse. 5. Plug the values into the formula to calculate the cosine, or use the cosine value to find missing side lengths. 6. For example, if $\theta = 30^\circ$ and the hypotenuse is 10 units, adjacent side = $10 \times \cos(30^\circ) = 10 \times \frac{\sqrt{3}}{2} = 5\sqrt{3}$ units. 7. Remember, cosine values range from -1 to 1 depending on the angle, but in a right triangle, the angle is between $0^\circ$ and $90^\circ$, so cosine is positive. 8. This basic understanding will help you solve right triangle problems with the cosine ratio.