diff --git a/education/math/MATH1060 (trig)/Identities.md b/education/math/MATH1060 (trig)/Identities.md index 63f13d8..60c710b 100644 --- a/education/math/MATH1060 (trig)/Identities.md +++ b/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 $cos\theta = -\frac{7}{25}$. \ No newline at end of file +$cos\theta = -\frac{7}{25}$ + +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: +$$ 1 - (-\frac{7}{25} = sin^2\theta $$