Topic Details (Notes format)

How to Use the Law of Sines in Any Triangle

Subject: Mathematics

Book: Maths Mastery

The Law of Sines states that in any triangle with sides a, b, c opposite angles A, B, C, we have a/sin(A) = b/sin(B) = c/sin(C). This allows you to find unknown angles or sides if you have at least one pair of angle-side. For instance, if angle A=30° and side a=10, and angle B=50°, you can solve for side b = (sin(B)/sin(A)) × a. This formula is key in navigation (bearing angles), astronomy (celestial triangles), and surveying. Mastery ensures quick and precise resolution of non-right triangles that commonly arise in real-world geometry tasks.

Practice Questions

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If a:b = 5:7 and b:c = 6:11, what is a:c?

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If sin(θ) = 3/5 and θ is an acute angle, what is tan(θ)?

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