Answer:
x = -2, x = 3 − i√8, and x = 3 + i√8
Step-by-step explanation:
g(x) = x³ − 4x² − x + 22
This is a cubic equation, so it must have either 1 or 3 real roots.
Using rational root theorem, we can check if any of those real roots are rational. Possible rational roots are ±1, ±2, ±11, and ±22.
g(-1) = 18
g(1) = 18
g(-2) = 0
g(2) = 12
g(-11) = 1782
g(11) = 858
g(-22) = -12540
g(22) = 8712
We know -2 is a root. The other two roots are irrational. To find them, we must find the other factor of g(x). We can do this using long division, or we can factor using grouping.
g(x) = x³ − 4x² − 12x + 11x + 22
g(x) = x (x² − 4x − 12) + 11 (x + 2)
g(x) = x (x − 6) (x + 2) + 11 (x + 2)
g(x) = (x (x − 6) + 11) (x + 2)
g(x) = (x² − 6x + 11) (x + 2)
x² − 6x + 11 = 0
Quadratic formula:
x = [ 6 ± √(36 − 4(1)(11)) ] / 2
x = (6 ± 2i√8) / 2
x = 3 ± i√8
The three roots are x = -2, x = 3 − i√8, and x = 3 + i√8.
Sub y = 0 in to find x intercept and x = 0 in to find y intercept
Answer:
-1/3
Step-by-step explanation:
The slope of the line has the form y = mx + b where m is the slope. Here the slope is m = 3. A line perpendicular to it will have a negative reciprocal slope. The negative reciprocal of 3 is -1/3.
The expression that is most useful for finding the year where the population was at a minimum would be 8(x − 9)² + 216.
Given expression 8x² − 144x + 864 is used to approximate a small town's population in thousands from 1998 to 2018, where x represents the number of years since 1998.
<h3>What is a quadratic equation?</h3>
A quadratic equation is the second-order degree algebraic expression in a variable. the standard form of this expression is ax² + bx + c = 0 where a. b are coefficients and x is the variable and c is a constant.
Given expression is 8x² − 144x + 864
Let y = 8x² − 144x + 864
also, y - 864 = 8x² - 144x
by Extracting common factor 8 on the right side
y - 864 = 8(x² - 18x)
Add (18/2)² on both sides, we get
y - 864 + 8(18/2)² = 8 (x² - 18x + 81²)
y - 864 + 648 = 8 (x² - 8x + 9)
on simplification
y - 216 = 8 (x - 9)²
y = 8(x - 9)² + 216
therefore, y = 8 (x - 9)² + 216
The expression that is most useful for finding the year where the population was at a minimum would be 8(x − 9)² + 216.
Learn more about a quadratic equation here:
brainly.com/question/2263981
Answer:
8
Step-by-step explanation:
2 times 4 is 8
