Find the Value of Theta in Degrees and Radians in First Quadrant

The video tutorial explains how to find the angle Theta in the first quadrant where the cosine equals sqrt 2 / 2. It begins by introducing the problem and constructing the first quadrant of the unit circle. The cosine of an angle is explained as the X coordinate on the unit circle. The tutorial then demonstrates how to find the angle by identifying when the X coordinate equals sqrt 2 / 2, concluding that the angle is 45 degrees or π/4 radians.

What is the main goal of the problem discussed in the first section?

• To find the sine of an angle

• To determine the angle Theta where cosine equals sqrt 2 / 2

• To calculate the tangent of an angle

• To find the area of the unit circle

In the context of the unit circle, what does the cosine of an angle represent?

• The Y coordinate of the point

• The circumference of the circle

• The X coordinate of the point

• The radius of the circle

How can you determine the angle when the X coordinate is sqrt 2 / 2 on the unit circle?

• By finding the Y coordinate

• By identifying the angle as 90 degrees

• By checking when the X coordinate equals sqrt 2 / 2

• By calculating the circumference

What is the angle in degrees when the cosine equals sqrt 2 / 2?

• 30 degrees

• 90 degrees

• 60 degrees

• 45 degrees

What is the angle in radians when the cosine equals sqrt 2 / 2?

• π/2 radians

• π/6 radians

• π/3 radians

• π/4 radians