Using trig ratios of complementary angles - Example 1

Evaluating sin 18 / cos 72 - different ways to evaluate
We have learn in this video 'Trigonometric ratios of Complementary angles'
• Trigonometric ratios o...
that Cosine (cos) is the complement of Sine (sin)
Cotangent (cot) is the complement of tangent(tan)
Cosecant (csc) is the complement of secant (sec) Missed the previous lesson/video?
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