Answer:
Step-by-step explanation:
Firstly, note that -2i really is just z = 0 + (-2)i, so we see that Re(z) = 0 and Im(z) = -2.
When we're going from Cartesian to polar coordinates, we need to be aware of a few things! With Cartesian coordinates, we are dealing explicitly with x = blah and y = blah. With polar coordinates, we are looking at the same plane but with angle and magnitude in consideration.
Graphing z = -2i on the Argand diagram will look like a segment of the y axis. So we ask ourselves "What angle does this make with the positive x axis? One answer you could ask yourself is -90°! But at the same time, it's 270°! Why do you think this is the case?
What about the magnitude? How far is "-2i" stretched from the typical "i". And the answer is -2! Well... really it gets stretched by a factor of 2 but in the negative direction!
Putting all of this together gives us:
z = |mag|*(cos(angle) + isin(angle))
= 2*cos(270°) + isin(270°)).
To verify, let's consider what cos(270°) and sin(270°) are.
If you graph cos(x) and look at 270°, you get 0.
If you graph sin(x) and look at 270°, you get -1.
So 2*(cos(270°) + isin(270°)) = 2(0 + -1*i) = -2i as expected.
<h3>
Answer: 20</h3>
Explanation:
For any rectangle, the diagonals are the same length.
AC = BD
7x-35 = 3x+45
7x-3x = 45+35
4x = 80
x = 80/4
x = 20
Answer:
SE = 0.025
Step-by-step explanation:
We are given;
Sample mean; x¯ = 14.52
Sample standard deviation; s = 0.075
Sample size; n = 9
Now,formula for standard error of sample mean is;
SE = s/√n
SE = 0.075/√9
SE = 0.075/3
SE = 0.025
The question is, "how many ways ...".
There are as many ways to solve a math problem as you can think of. (Some are shorter or easier than others.)
Essentially, an infinite number.
