Chapter 7.6 Cosine

Front

What is the cosine of an angle in a right triangle?

Back

The cosine of an angle is the ratio of the length of the adjacent side to the length of the hypotenuse.

Front

How do you calculate the cosine of an angle using a calculator?

Back

To calculate the cosine of an angle, ensure the calculator is in the correct mode (degrees or radians) and input the angle value, then press the cosine function key.

Front

What is the range of the cosine function?

Back

The range of the cosine function is from -1 to 1.

Front

What is the cosine of 0 degrees?

Back

The cosine of 0 degrees is 1.

Front

What is the cosine of 90 degrees?

Back

The cosine of 90 degrees is 0.

Front

What is the cosine of 180 degrees?

Back

The cosine of 180 degrees is -1.

Front

What is the relationship between cosine and the unit circle?

Back

In the unit circle, the cosine of an angle corresponds to the x-coordinate of the point on the circle at that angle.

Front

If cos X = 0.5, what is the angle X in degrees?

Back

X = 60 degrees or 300 degrees.

Front

What is the cosine rule in triangle calculations?

Back

The cosine rule states that c² = a² + b² - 2ab*cos(C), where c is the side opposite angle C.

Front

How can you find the cosine of an angle using a right triangle?

Back

Identify the lengths of the adjacent side and the hypotenuse, then use the formula cos(angle) = adjacent/hypotenuse.