Complementary Angles
ICSE · Class 9 · Mathematics
All formulas from Complementary Angles in ICSE Class 9 Mathematics. Key equations, constants, and identities for board exam preparation.
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Core Definitions
Complement of θ° = (90 − θ)°
sin(90° − θ) = cos θ
cos(90° − θ) = sin θ
tan(90° − θ) = cot θ
cot(90° − θ) = tan θ
Triangle-Based Trigonometric Relations
sin θ = AB/AC
cos(90° − θ) = AB/AC
tan θ = AB/BC
cot(90° − θ) = AB/BC
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