Acute Angles and Trigonometric Functions

The video tutorial explains the concept of related acute angles and how to express trigonometric functions using these angles. It covers the definition of acute angles, the rules of trigonometric ratios in different quadrants, and provides examples for sine, cosine, tangent, and secant functions. The tutorial emphasizes understanding the quadrant in which the angle lies to determine the sign of the trigonometric function.

What is the main topic discussed in the video?

• Using related acute angles to find equivalent expressions

• Understanding acute angles

• Learning about trigonometric functions

• Exploring the properties of angles

Which of the following is true about acute angles?

• They are always greater than 90 degrees

• They can be any angle

• They are always negative

• They are always less than 90 degrees

What is the range of an acute angle?

• Greater than 180 but less than 270 degrees

• Greater than 90 but less than 180 degrees

• Greater than 0 but less than 90 degrees

• Greater than 270 but less than 360 degrees

In which quadrant are all trigonometric ratios positive?

• Quadrant I

• Quadrant III

• Quadrant II

• Quadrant IV

What does the CAST rule help determine?

• The length of a side in a triangle

• The sign of trigonometric functions in different quadrants

• The size of an angle

• The type of angle

What is the related acute angle for sine 160 degrees?

• 20 degrees

• 40 degrees

• 10 degrees

• 30 degrees

What is the equivalent expression for sine 160 degrees using an acute angle?

• sine 50 degrees

• sine 40 degrees

• sine 30 degrees

• sine 20 degrees

What is the related acute angle for sine 300 degrees?

• 50 degrees

• 60 degrees

• 80 degrees

• 70 degrees

What is the equivalent expression for sine 300 degrees using an acute angle?

• sine 50 degrees

• negative sine 50 degrees

• sine 60 degrees

• negative sine 60 degrees

What is the related acute angle for cosine 210 degrees?

• 50 degrees

• 20 degrees

• 40 degrees

• 30 degrees