Solve a trig equation by factoring a perfect square trinomial

The video tutorial covers the process of factoring algebraic expressions, initially without using cosines, and then transitions to factoring with cosines. It explains the concept of a perfect square trinomial and demonstrates solving trigonometric equations where the cosine of X equals 1/2. The tutorial also discusses identifying angles in different quadrants and corrects common mistakes in angle identification.

What is a perfect square trinomial?

• A trinomial that can be factored into two identical binomials.

• A trinomial with three different terms.

• A trinomial with only one term.

• A trinomial that cannot be factored.

When solving the equation 2cos(X) - 1 = 0, what is the value of cos(X)?

• -1/2

• 1/2

• 1

• 0

In which quadrants is cosine positive?

• First and fourth

• Second and third

• First and second

• Third and fourth

What is the reference angle for cosine being 1/2 in the fourth quadrant?

• π/3

• π/2

• π/6

• π/4

What are the correct angles for X when cos(X) = 1/2 within the interval [0, 2π]?

• π/4 and 7π/4

• π/3 and 5π/3

• π/3 and 11π/3

• π/6 and 5π/6