Trig Evaluation
1. Stating the problem: Calculate the values of the following expressions involving trigonometric functions:
a. $\sin 60^\circ \cos 45^\circ + \sec 30^\circ \cot 60^\circ$
b. $\frac{\sin 30^\circ + \cos^2 45^\circ + \tan^2 60^\circ}{\csc 30^\circ \cot 45^\circ}$
2. Solve part (a):
- Recall values: $\sin 60^\circ = \frac{\sqrt{3}}{2}$, $\cos 45^\circ = \frac{\sqrt{2}}{2}$, $\sec 30^\circ = \frac{1}{\cos 30^\circ} = \frac{2}{\sqrt{3}}$, $\cot 60^\circ = \frac{1}{\tan 60^\circ} = \frac{1}{\sqrt{3}}$
- Compute each term: $\sin 60^\circ \cos 45^\circ = \frac{\sqrt{3}}{2} \times \frac{\sqrt{2}}{2} = \frac{\sqrt{6}}{4}$
- Compute $\sec 30^\circ \cot 60^\circ = \frac{2}{\sqrt{3}} \times \frac{1}{\sqrt{3}} = \frac{2}{3}$
- Sum: $\frac{\sqrt{6}}{4} + \frac{2}{3} = \frac{3\sqrt{6}}{12} + \frac{8}{12} = \frac{3\sqrt{6} + 8}{12}$
3. Solve part (b):
- Recall values: $\sin 30^\circ = \frac{1}{2}$, $\cos 45^\circ = \frac{\sqrt{2}}{2}$ so $\cos^2 45^\circ = \left(\frac{\sqrt{2}}{2}\right)^2 = \frac{1}{2}$
- $\tan 60^\circ = \sqrt{3}$ so $\tan^2 60^\circ = 3$
- Numerator: $\sin 30^\circ + \cos^2 45^\circ + \tan^2 60^\circ = \frac{1}{2} + \frac{1}{2} + 3 = 4$
- Denominator: $\csc 30^\circ = \frac{1}{\sin 30^\circ} = 2$, $\cot 45^\circ = 1$
- Denominator: $2 \times 1 = 2$
- Fraction: $\frac{4}{2} = 2$
Final answers:
a. $\frac{3\sqrt{6} + 8}{12}$
b. $2$