Rule needed: i^2 = -1
Standard form a + bi
(3 + 2i)(7 - 5i) FOIL
3 * 7 = 21
3 * - 5i = - 15i
2i * 7 = 14i
2i * -5i = - 10i^2 = - 10 * -1 = 10
Putting it all back together.
31 - i
Answer: 
<u>Step-by-step explanation:</u>
The general form of a sin/cos function is: y = A sin/cos (Bx-C) + D where the period (P) = 2π ÷ B
In the given function, 
→ 
Half of that period is: 
Calculate the period for each of the options to find a match:
We can solve this two different ways. I'll do both, and you choose which one makes the most sense:
We can divide the fraction 3/4 by 12. remember, when we divide fractions, we flip the second fraction and change the sign to multiplication:
3/4 ÷12 [starting equation]
3/4 x 1/12 [flip and change sign]
3/48 [now reduce]
1/16 Each step takes 1/16 of an hour.
1/16 x 60 = 3 3/4, or 3.75 minutes
Second way:
3/4 of an hour is 3/4 of 60...45 minutes.
Still, we divide out:
45 ÷ 12 [starting equation]
3 9/12 [divide with remainder]
3 3/4 minutes...3.75 minutes
Step-by-step explanation:
A=P(1+i)^n
=5,000(1+5%/4)^10×4
=$8,218.10
