Answer:
The sum of the expression (8 - 4i) + (-2 +7i) is (6 + 3i)
Step-by-step explanation:
In the complex numbers (a + bi) and (c + di), we can add the real parts together and the imaginary parts together, so their sum is
(a + bi) + (c + di) = (a + c) + (b + d)i
Let us use this fact to solve our question
∵ The complex numbers are (8 - 4i) and (-2 + 7i)
∴ Their sum = (8 - 4i) + (-2 + 7i)
∵ The real parts are 8 and -2
∵ 8 + -2 = 8 - 2 = 6
∴ The sum of the real parts is 6
∵ The imaginary parts are -4i and 7i
∵ -4i + 7i = 3i
∴ The sum of the the imaginary parts is 3i
∵ (8 - 4i) + (-2 + 7i) = (8 - 2) + (-4 + 7)i
∴ (8 - 4i) + (-2 + 7i) = 6 + 3i
∴ The sum of the expression (8 - 4i) + (-2 +7i) is (6 + 3i)
PPLMway will help
Step-by-step explanation:
Answer:
Step-by-step explanation:
Assuming a normal distribution for the distribution of the points scored by students in the exam, the formula for normal distribution is expressed as
z = (x - u)/s
Where
x = points scored by students
u = mean score
s = standard deviation
From the information given,
u = 70 points
s = 10.
We want to find the probability of students scored between 40 points and 100 points. It is expressed as
P(40 lesser than x lesser than or equal to 100)
For x = 40,
z = (40 - 70)/10 =-3.0
Looking at the normal distribution table, the corresponding z score is 0.0135
For x = 100,
z = (100 - 70)/10 =3.0
Looking at the normal distribution table, the corresponding z score is 0.99865
P(40 lesser than x lesser than or equal to 100) = 0.99865 - 0.0135 = 0.98515
The percentage of students scored between 40 points and 100 points will be 0.986 × 100 = 98.4%
Answer:
78 i believe
Step-by-step explanation:
Answer:
optionb
Step-by-step explanation:
