Values of Sine, Cosine, and Tangent for 30°, 45°, and 60°
Big Idea: Certain "special" angles appear so frequently in mathematics, science, and engineering that memorizing their sine, cosine, and tangent values will save you enormous time and deepen your understanding of trigonometry.
📐 Quick Review: What Are Trig Ratios?
In a right triangle, for a given acute angle $\theta$:
- $\sin\theta = \dfrac{\text{Opposite}}{\text{Hypotenuse}}$
- $\cos\theta = \dfrac{\text{Adjacent}}{\text{Hypotenuse}}$
- $\tan\theta = \dfrac{\text{Opposite}}{\text{Adjacent}}$
Remember the mnemonic: SOH-CAH-TOA
Interactive visualization — available in the full lesson