Memorizing the Trigonometric Unit Circle Made Easy

Professor Dave explains the unit circle, a fundamental concept in trigonometry. He covers the basics of sine and cosine, using the SOHCATOA mnemonic, and demonstrates how to memorize the unit circle's values. The video also extends this knowledge to other quadrants and provides practical applications for solving trigonometric problems.

What is the radius of the unit circle?

• 0

• 1

• π

• 2

What does the sine of an angle in the unit circle represent?

• Length of the adjacent leg

• X coordinate of the point

• Y coordinate of the point

• Length of the hypotenuse

What is the cosine of zero in the unit circle?

• π

• -1

• 1

• 0

How is the sine of π/6 represented?

• 1/2

• √3/2

• √2/2

• -1/2

What pattern is used to remember sine and cosine values in the unit circle?

• Counting up from zero to four

• Alternating positive and negative values

• Multiples of π

• Numerical sequence of roots over two

In which quadrant do both sine and cosine values become negative?

• I

• II

• III

• IV

What is the sine value of an angle located in the second quadrant?

• Undefined

• Negative

• Positive

• Zero

How do you find the tangent of an angle using the unit circle?

• Divide the Y coordinate by the X coordinate

• Multiply the X and Y coordinates

• Add the X and Y coordinates

• Divide the X coordinate by the Y coordinate

What is the result of the tangent of 14π/3?

• √3

• -√3

• -1/2

• 1/2

What is the cosecant of -17π/4?

• -2

• √2

• -√2

• 2