vault backup: 2024-09-23 11:41:45

education/math/MATH1060 (trig)/Identities.md

@@ -55,4 +55,9 @@ $$ \sqrt{\frac{576}{49}} = tan\theta $$
 $\sqrt{576} = 24$ and $\sqrt{49} = 7$, so:
 $$ tan\theta = \frac{24}{7} $$
 2. To find $cos\theta$, because $sec$ is the inverse of $cos$, we can use the identity $sec\theta = \frac{1}{cos\theta}$:
-So $cos\theta = -\frac{7}{25}$.
+$cos\theta = -\frac{7}{25}$
+
+3. To find $sin\theta$, we can use the trig identity $sin^2\theta + cos^2\theta = 1$:
+$$ sin^2\theta + (-\frac{7}{25}) = 1 $$
+Rearranging, we get:
+$$ 1 - (-\frac{7}{25} = sin^2\theta $$