Let's find the value of cosine of 20 degrees. We can visualize this using the unit circle. In the unit circle, 20 degrees is in the first quadrant. The cosine of an angle gives us the x-coordinate of the point where the angle intersects the circle.
To calculate the exact value of cosine 20 degrees, we can use a scientific calculator or trigonometric tables. First, make sure your calculator is set to degree mode. Then enter cosine of 20 degrees and press equals. The result is approximately 0.93969.
Let's verify our result and understand its properties. Since 20 degrees is in the first quadrant, cosine is positive. The value 0.93969 makes sense because it's close to cosine of 0 degrees, which equals 1. This confirms our calculation is correct.
To summarize what we've learned: cosine of 20 degrees represents the x-coordinate of a point on the unit circle. Using a calculator, we found that this value is approximately 0.93969. This positive result makes sense because 20 degrees is in the first quadrant where all trigonometric functions are positive.