First lets see the pythagorean identities
So if we have to solve for sin theta , first we move cos theta to left side and then take square root to both sides, that is
Now we need to check the sign of sin theta
First we have to remember the sign of sin, cos , tan in the quadrants. In first quadrant , all are positive. In second quadrant, only sin and cosine are positive. In third quadrant , only tan and cot are positive and in the last quadrant , only cos and sec are positive.
So if theta is in second quadrant, then we have to positive sign but if theta is in third or fourth quadrant, then we have to use negative sign .
Answer:
(A) the specific number of siblings for each randomly selected student
Step-by-step explanation:
First Timothy wants to estimate the mean number of siblings for each student in his school
So he selected a random sample of 75 students, then recorded the number of siblings they have
He later find the mean.
You can see the mean was obtained from the selected group not all students in the school hence option D and E are not correct.
Option A clearly indicates a mean was obtained for the siblings that were from the randomly selected students.
It’s easiest to think about it this way:
If the pond is 15 feet wide, then adding 3 feet to each side would increase the side length to the square by six feet (3 feet on each side). This makes the area within the square equal to 18x18 feet, or 324 square feet. But, this isn’t the area of the sidewalk, it’s the area of the sidewalk plus the area of the pool.
The pool is fifteen feet wide, which means that it has an area of 225 square feet. So, to find the area of the side walk, we can subtract the area of the pool from the area of the pool and sidewalk, which will give us the area of the sidewalk by itself.
324-225=99 square feet.
The pool has an area of 225 square feet, and the sidewalk has an area of 99 feet.
