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.
First distribute the 2, then add 7 to that side, so you have 2g+17=-4g+g , subtract 2g and it should be easy to find from there lol
Using a t-distribution calculator and finding the p-value, the correct option regarding the conclusion is given by:
a) the p-value is 0.02. We reject h0 at the 5% significance level because the p-value 0.02 is less than 0.05.
<h3>What is the relation between the p-value and the conclusion?</h3>
It also involves the significance level, as follows.
- If the p-value is less than the significance level, we reject the null hypothesis
.
- If it is more, we do not reject.
In this problem, a t-distribution calculator for a right-tailed with <em>t = 2.15 and 25 - 1 = 24 df</em> is used to find a p-value of 0.02.
It is less than 0.05, hence option a is correct.
More can be learned about p-values at brainly.com/question/26454209
