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Mathematics
Quick fact
The angle addition formula for sine, sin(A+B) = sin A cos B + cos A sin B, is not just a rule—it can be derived from the unit circle by comparing the coordinates of rotated points.
Why this is interesting
You know that sin²θ + cos²θ = 1, but have you ever wondered why it's true for every angle? And where do the double-angle formulas come from? The answers lie in a simple circle.
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Subjects · study & training · careers
Choose something you are considering. FACTREE will give you a clear picture of what it contains, how its main parts connect and where it could lead.
This private catalogue connects 31 subjects, study routes and careers across six broad areas. Public Maps and learner routes remain off.
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Open a subject to see its complete shape at a glance. You can always return here and choose something else.
See what programming involves, how its main areas connect, and whether you find the knowledge interesting enough to take it further.
Structuring the Programming Map…
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