Solving an equation with cosine of a multiple angle

The video tutorial explains how to solve a cosine equation involving a multiple angle, specifically 3T. It emphasizes the importance of inverse operations and common mistakes students make, such as dividing by three prematurely. The tutorial guides through isolating the cosine function, finding the values of cosine at 1/2, and determining the angles. It concludes with finalizing the solution by dividing by three and explaining the concept of infinite solutions.

What is the first step in solving an equation involving a cosine function?

• Divide by the coefficient of the variable

• Isolate the cosine function

• Add a constant to both sides

• Use the inverse cosine function

Why can't you divide by the coefficient of the variable inside the cosine function immediately?

• Because the cosine function must be undone first

• Because it will result in a complex number

• Because the variable is not isolated

• Because it will change the function to sine

What are coterminal angles?

• Angles that have the same sine value

• Angles that differ by a multiple of 2π

• Angles that are complementary

• Angles that are supplementary

After evaluating the cosine function, what is the next step in solving for the variable?

• Subtract a constant from both sides

• Multiply by the coefficient of the variable

• Add 2π to the solution

• Divide by the coefficient of the variable

How are infinite solutions represented in the context of solving trigonometric equations?

• By using a range of angles

• By adding multiples of π

• By adding multiples of 2π

• By using a single angle