Sine of Complement equals Cosine/Examples/2 Theta minus 90
Jump to navigation
Jump to search
Example of Sine of Complement equals Cosine
- $\map \sin {2 \theta - 90 \degrees} = -\cos 2 \theta$
Proof
\(\ds \map \sin {2 \theta - 90 \degrees}\) | \(=\) | \(\ds -\map \sin {90 \degrees - 2 \theta}\) | Sine Function is Odd | |||||||||||
\(\ds \) | \(=\) | \(\ds -\cos 2 \theta\) | Sine of Complement equals Cosine |
$\blacksquare$
Sources
- 1953: L. Harwood Clarke: A Note Book in Pure Mathematics ... (previous) ... (next): $\text V$. Trigonometry: Exercise $\text {XXXI}$: $10.$