ANSWER
x = ±1 and y = -4.
Either x = +1 or x = -1 will work
EXPLANATION
If -3 + ix²y and x² + y + 4i are complex conjugates, then one of them can be written in the form a + bi and the other in the form a - bi. In other words, between conjugates, the imaginary parts are same in absolute value but different in sign (b and -b). The real parts are the same
For -3 + ix²y
⇒ real part: -3
⇒ imaginary part: x²y
For x² + y + 4i
⇒ real part: x² + y (since x, y are real numbers)
⇒ imaginary part: 4
Therefore, for the two expressions to be conjugates, we must satisfy the two conditions.
Condition 1: Imaginary parts are same in absolute value but different in sign. We can set the imaginary part of -3 + ix²y to be the negative imaginary part of x² + y + 4i so that the
x²y = -4 ... (I)
Condition 2: Real parts are the same
x² + y = -3 ... (II)
We have a system of equations since both conditions must be satisfied
x²y = -4 ... (I)
x² + y = -3 ... (II)
We can rearrange equation (II) so that we have
y = -3 - x² ... (II)
Substituting into equation (I)
x²y = -4 ... (I)
x²(-3 - x²) = -4
-3x² - x⁴ = -4
x⁴ + 3x² - 4 = 0
(x² + 4)(x² - 1) = 0
(x² + 4)(x-1)(x+1) = 0
Therefore, x = ±1.
Leave alone (x² + 4) as it gives no real solutions.
Solve for y:
y = -3 - x² ... (II)
y = -3 - (±1)²
y = -3 - 1
y = -4
So x = ±1 and y = -4. We can confirm this results in conjugates by substituting into the expressions:
-3 + ix²y
= -3 + i(±1)²(-4)
= -3 - 4i
x² + y + 4i
= (±1)² - 4 + 4i
= 1 - 4 + 4i
= -3 + 4i
They result in conjugates
<h2>The Correct answer is B)</h2><h2>This answer is verified by brainy.Com✓</h2>
Answer:
0.8%
Step-by-step explanation:
Because they are two independent events, the final probability is the product of the probability of each event.
First event:
The complement of a student being male is that he is female.
Therefore, if 60% is male, the remaining 100% is 40%, meaning that 40% of the students are female.
Second event:
If she's taller than 5'4", we're told she has a 2% chance of being a woman.
Therefore the final probability is:
0.4*0.02 = 0.008
That is, the probability that it is female and that it is over 1.6 meters tall is 0.8%.
Answer:
Shorter piece length is 18 inches
Step-by-step explanation:
Let's marked first piece with x and second with y
x + y = 42
Given ratio is x : y = 3 : 4
From this proportion we get
x = 3 c and y = 4 c where c is coefficient of proportionality
when we replace this in initial equation we get
3 c + 4 c = 42 => 7 c = 42 => c = 42/7 = 6 c = 6
x = 3 · 6 = 18 inches and z = 4 · 6 = 24 inches
shorter piece is x = 18 inches
God with you!!!
Answer:
mean
Step-by-step explanation:
mean .
mean is regarded as the average value calculated from a data set .
mean = total sum of values / total number of values.
