The video discusses the marking of trigonometric proofs, presenting two methods: dividing the left-hand side by the right-hand side and subtracting the right-hand side from the left-hand side. The teacher prefers the subtraction method due to the potential issues with division, such as undefined values. The video emphasizes the importance of choosing safer mathematical operations to avoid errors in proofs.

What are the two methods suggested for proving trigonometric identities?

• Using integration and differentiation

• Using division and subtraction

• Using multiplication and addition

• Using substitution and elimination

What is the teacher's preferred method for proving trigonometric identities?

• Using numerical approximation

• Using graphical representation

• Using division to equate both sides

• Starting from one side and simplifying to the other

Why is division considered risky in trigonometric proofs?

• It introduces undefined points

• It is too complex to solve

• It requires advanced calculus

• It is not allowed in exams

What is a potential issue when using division in functions?

• It results in a constant function

• It makes the function non-linear

• It simplifies the function too much

• It can create holes in the graph

Which method is considered safer for proving inequalities?

• Using integration

• Using multiplication

• Using division

• Using subtraction

What is a common approach to prove that one value is greater than another?

• Consider the sum and show it is negative

• Consider the difference and show it is positive

• Consider the quotient and show it is undefined

• Consider the product and show it is zero

Why is subtraction preferred over division in trigonometric proofs?

• It is easier to calculate

• It does not introduce undefined points

• It is faster to solve

• It is more visually appealing

What is the main takeaway regarding the use of division in proofs?

• Avoid unnecessary division to prevent undefined solutions

• Division should be used only in calculus

• Use division to simplify calculations

• Division is always the best method

What is the teacher's final opinion on the two methods discussed?

• Neither method is recommended

• Both methods are equally valid

• Division is more accurate

• Subtraction is safer and preferred

What is a key advantage of using subtraction in proofs?

• It is more intuitive

• It requires less algebra

• It is more complex

• It avoids introducing restrictions