The domain for the rational expression as given in the task content is; All real numbers except -5.
<h3>Domain of Rational functions</h3>
The domain of a rational function such as that given in the task content includes all possible values of the variable except that which renders the expression undefined.
On this note, the expression is undefined when, 3x + 15 = 0.
Hence, the domain is All real numbers except -5.
Read more on rational functions;
brainly.com/question/13763081
I assume the answer is 1/4
Trigonometry:
We know that csc x = 1 / sin x and π = 180°;
sin 5π/ 6 = sin 150° = 1/2
csc 2π / 3 = 1 / sin 120° = 1 / √3/2 = 2 / √3
Finally:
4 · 1/2 + 7 · ( 2 / √3 )² = 2 + 7 · 4/3 =
= 2 + 28/3 = 2 + 9 1/3 = 11 1/3
