Using the Cosine Ratio in Right Triangles

The video tutorial explains how to solve a problem involving a ladder leaning against a house using the cosine ratio. It introduces the concept of right triangles and the cosine ratio, reviews the sine ratio, and demonstrates the application of the cosine ratio in various examples. The tutorial also clarifies common misunderstandings about the cosine ratio and concludes by solving the ladder problem, determining the necessary ladder length using trigonometric principles.

What is the height of the house in the problem introduced at the beginning?

• 12 feet

• 10 feet

• 15 feet

• 20 feet

Which of the following best describes the sine ratio?

• Length of the hypotenuse divided by the side adjacent to the angle

• Length of the side opposite the angle divided by the hypotenuse

• Length of the hypotenuse divided by the side opposite the angle

• Length of the side adjacent to the angle divided by the hypotenuse

In the example of triangle ABC, what is the sine of the 38-degree angle approximately?

• 0.714

• 0.814

• 0.614

• 0.514

What is the cosine ratio in a right triangle?

• Length of the side adjacent to the angle divided by the hypotenuse

• Length of the hypotenuse divided by the side opposite the angle

• Length of the side opposite the angle divided by the hypotenuse

• Length of the hypotenuse divided by the side adjacent to the angle

Which angle is used in the examples to demonstrate the cosine ratio?

• 45 degrees

• 40 degrees

• 35 degrees

• 30 degrees

What is the approximate length of the ladder needed to reach the roof?

• 12.65 feet

• 13.65 feet

• 14.65 feet

• 15.65 feet

Why might it be advisable to get a ladder slightly longer than 14.65 feet?

• To make it easier to climb

• To allow for future house extensions

• To account for measurement errors

• To ensure it reaches the roof safely