There are two ways to work this out: normal variables or using "imaginary" numbers.
Normal variables:
![(7+2i)(3-i)\\(7*3)+[7*(-i)]+(3*2i)+[2i*(-i)]\\21-7i+6i-2i^{2}\\\\21-i-2i^{2}](https://tex.z-dn.net/?f=%20%287%2B2i%29%283-i%29%5C%5C%287%2A3%29%2B%5B7%2A%28-i%29%5D%2B%283%2A2i%29%2B%5B2i%2A%28-i%29%5D%5C%5C21-7i%2B6i-2i%5E%7B2%7D%5C%5C%5C%5C21-i-2i%5E%7B2%7D)
Imaginary numbers:
Using the result from earlier:
Now since
, then the expression becomes:
Answer:
y < x
y < 4
Step-by-step explanation:
Dotted line means < or >, and since the shaded region is below the lines y = 4 and y = x, the answer is A.
Answer:
c
Step-by-step explanation:
cvvvbbnh
Answer:
Option C: n = 32; p^ = 0.4
Step-by-step explanation:
The normal curve can be used in this case if; np ≥ 10 or n(1 - p) ≥ 10
A) For n = 28 and p = 0.3;
np = 28 × 0.3 = 8.4 < 10
Thus, it can't be used.
B) For n = 28 and p = 0.9;
np = 28 × 0.9 = 25.2 > 10 Ok
n(1 - p) = 28(1 - 0.9) = 2.8 Not Ok
Thus, it can't be used
C) For n = 32 and p = 0.4
np = 32 × 0.4 = 12.8 > 10 Ok
n(1 - p) = 32(1 - 0.4) = 19.2 > 10 Ok
Thus, it can be used
D) For n = 32 and p = 0.2
np = 32 × 0.2 = 6.4 < 10 Not Ok
Thus it can't be used.
