The video tutorial explains how to apply the sum and difference formulas in trigonometry, focusing on sine and cosine functions. It demonstrates the use of brackets to ensure correct subtraction and the application of the distributive property. The tutorial also covers solving trigonometric equations where cosine of x equals 1/2, identifying the angles that satisfy this condition. Clarifications are provided on the simplification of terms involving sine and cosine.

What is the primary reason for using different formulas in trigonometric expressions?

• To make calculations faster

• To avoid using brackets

• To handle addition and subtraction differently

• To simplify the expression

Why is it important to use brackets when applying the sum and difference formulas?

• To distribute negative signs correctly

• To avoid forgetting terms

• To make the expression look neat

• To ensure the correct order of operations

What happens when you distribute a negative sign across terms in a bracket?

• All terms become positive

• All terms become negative

• The signs of the terms are reversed

• The terms remain unchanged

When cosine of x equals 1/2, what are the possible angles between 0 and 2π?

• π/2 and 3π/2

• π/6 and 11π/6

• π/4 and 7π/4

• π/3 and 5π/3

Why does the sine of π/6 equal 1/2?

• It is derived from the cosine value

• It is an approximation

• It simplifies the expression

• It is a standard trigonometric value