answers are in the pictures

Using the fact that cos is 2π-periodic, we have

That is,
for any
and integer
.

We get 2 solutions in the interval [0, 2π] for
and
,

Answer:
The solutions are:

Step-by-step explanation:
We have the following quadratic equation

We can rewrite the equation as follows

Now we use the quadratic formula to solve the equation
For an equation of the form
the quadratic formula is:

In this case:

Then:





Answer:
8w : 3.8974342 ≈ 3.9 or 4 (hope it help)
Step-by-step explanation:
1w : 2
2w : 2 + 10% = 2.2
3w : 2.2 + 10% = 2.42
4w : 2.42 + 10% = 2.662
5w : 2.662 + 10% = 2.9282
6w : 2.9282 + 10% = 3.22102
7w : 3.22102 + 10% = 3.543122
8w : 3.543122 + 10% = 3.8974342
3.8974342 ≈ 3.9 or 4
So basically what you have to do is first identify all of the sides or angles that equal eachother then you can see if you did a side side and side in a row etc, like 44 would be SAS because the vertical angles would be inbetween the two sides. 46 would be SSS because after you make the line in the middle for reflexive property you can see that there are three sides in a row. If this didnt help i recommend looking on Khan Academy