Question

1. \\(cos c\\)

\\(c\\)---30---\\(a\\)
\\(c\\)---24---\\(b\\) (right angle at \\(b\\))
\\(b\\)---18---\\(a\\)

Explanation:

Step1: Recall cosine definition

For right triangle, $\cos C = \frac{\text{adjacent to } C}{\text{hypotenuse}}$

Step2: Identify sides for angle C

Adjacent side to $C$ is $24$, hypotenuse is $30$.

Step3: Calculate cos C

$\cos C = \frac{24}{30} = \frac{4}{5}$

Answer:

$\frac{4}{5}$