Subtracting two rational trigonometric expressions

The video tutorial explains the process of subtracting fractions with different denominators by finding the least common denominator (LCM). It demonstrates how to multiply denominators to achieve a common base and simplify the expression using the difference of squares. The tutorial further simplifies the expression using Pythagorean identities, ultimately arriving at a final simplified form involving tangent squared. The instructor emphasizes careful application of negative signs during subtraction to avoid errors.

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