Answer and step-by-step explanation:
The polar form of a complex number 
is the number 
where 
is called the modulus and 
is called the argument. You can switch back and forth between the two forms by either remembering the definitions or by graphing the number on Gauss plane. The advantage of using polar form is that when you multiply, divide or raise complex numbers in polar form you just multiply modules and add arguments.
(a) let's first calculate moduli and arguments
now we can write the two numbers as
(b) As noted above, the argument of the product is the sum of the arguments of the two numbers:
(c) Similarly, when raising a complex number to any power, you raise the modulus to that power, and then multiply the argument for that value.
![(z_1)^1^2=[4e^{-i\frac \pi6}]^1^2=4^1^2\cdot (e^{-i\frac \pi6})^1^2=2^2^4\cdot e^{-i(12)\frac\pi6}\\=2^2^4 e^{-i\cdot2\pi}=2^2^4](https://tex.z-dn.net/?f=%28z_1%29%5E1%5E2%3D%5B4e%5E%7B-i%5Cfrac%20%5Cpi6%7D%5D%5E1%5E2%3D4%5E1%5E2%5Ccdot%20%28e%5E%7B-i%5Cfrac%20%5Cpi6%7D%29%5E1%5E2%3D2%5E2%5E4%5Ccdot%20e%5E%7B-i%2812%29%5Cfrac%5Cpi6%7D%5C%5C%3D2%5E2%5E4%20e%5E%7B-i%5Ccdot2%5Cpi%7D%3D2%5E2%5E4)
Now, in the last step I've used the fact that 
, or in other words, the complex exponential is periodic with 
as a period, same as sine and cosine. You can further compute that power of two with the help of a calculator, it is around 16 million, or leave it as is.
The percentage of the radioactive isotope left is 25.0000%.
<h3>What is the half life?</h3>
The half life of a radioactive isotope is the time that will elapse before only half of the number of original isotopes will remain.
Now;
We are told that;
Half life (t1/2) = 55 days
Time taken (t) = 115 days
Ratio of isotope remaining = N/No
Thus;
N/No = (1/2)^t/t1/2
N/No = (1/2)^115/55
N/No = (1/2)^2
N/No =1/4
Hence, the percentage = 1/4 * 100/1 = 25.0000%
Learn more about half life of an isotope:brainly.com/question/16387602
#SPJ1
The correct answer for the question that is being presented above is this one: "b. $2.78." Andrew owns stock in Hyren Airlines and as a result gets paid dividends worth $539.70 every year. If Andrew owns 105 shares of Hyren Airlines, the dividend of each share yields <span>b. $2.78</span>
Answer:
This is a good tip and $18 is 18% of what the meal cost.
Step-by-step explanation:
On average the proper tip is 15% of the cost of your meal cost. In this case you have paid 18% of your meal cost.
300 tamales is what i got
let me know if its wrong
