Answer: Choice D
15(cos85° + i sin85°)
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Explanation:
Let's say we had these two general complex numbers, which are in polar form.
We can abbreviate them into the shorthand form
The notation "cis" stands for "cosine i sine".
Now that we have those complex numbers set up, multiplying them is as simple as saying this:
We do two basic things:
- Multiply the r values out front
- Add the theta values inside the the cis function
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With all that in mind, let's tackle the problem your teacher gave you.
The given complex numbers
abbreviate into
then those multiply to
which is why choice D is the final answer.
It's best to think of oddly shaped polygons as different simple shapes within itself. You can divide them into two rectangles, solve for their areas separately, then add them together. (Halves slip horizontally)
6*11 would be the top half, which equals 66 square units
It is not given the amount of units long the longest side is, but you can figure it out by adding the sides given above. (7, 11, and 6)
5*24 would be the bottom half; 120 square units
Add both areas together to get the overall area of the polygon given
66+120=186
His error is in step 3. The variable x is being multiplied by -7 and therefore he should have divided both sides by -7, not 7 as he did.
Answer:
Step-by-step explanation:
Answer: 
Step-by-step explanation:
- A coin has 2 sides. Which means the probability of the coin landing on one side will be 
.
- Since there are three coins, we multiply three times ( * * ) to get the answer of
