Answer:
Expand it.
(1+2i)^3 is equal to (1+2i)(1+2i)(1+2i).
Multiply everything out (being sure to multiply <em>every</em> term. (1+2i) * (1+2i) = 1+2i+2i+4i^2.
i is the square root of negative one, so i^2 is just -1. 1+2i+2i-4 is what you get from the first two, so now simplify that:
1-4 + 2i+2i = (-3+4i) and now multiply that by (1+2i):
(-3+4i) * (1+2i) = -3 - 6i +4i +8i^2.
Simplify again, and the answer is: -11-2i
Step-by-step explanation:
I hope this helps - really my only tip is don't spend time thinking about what i is, that just hurts your brain. Just remember that i^2 is equal to negative one, and treat it like regular multiplication and you will be fine.
Answer:
The 92% confidence interval for the true proportion of customers who click on ads on their smartphones is (0.3336, 0.5064).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
For this problem, we have that:
92% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
The lower limit of this interval is:
The upper limit of this interval is:
The 92% confidence interval for the true proportion of customers who click on ads on their smartphones is (0.3336, 0.5064).
The shape has 7 sides.
The sum of the interior angles is (7-2)180 = 5 * 180 = 900 degrees.
Divide the total sum by 7:
X = 900 /7 = 128.6 degrees.
6x + 4x+6 + 8x+3 = 63
6x+4x+8x = 63 - 3 - 6
18x = 54
x = 54/18
x = 3
Side AB = 6(3) = 18
Side AC = 4(3)+6 = 18
Side BC = 8(3)+3 = 27
