Which of the following is a solution to the inequality below?
2 answers:
You might be interested in
Hi there!
We can find the range using completing the square:
y = -x² - 2x + 8
Factor out a -1:
y = -(x² + 2x) + 8
Use the first two terms. Take the second term's coefficient, divide by 2, and square:
y = -(x² + 2x + 1) + 8
Remember to add by 1 because we cannot randomly add an additional number into the equation:
y = -(x² + 2x + 1) + 8 + 1
Simplify:
y = -(x + 1)² + 9
Since the graph opens downward (negative coefficient), the range is (-∞, 9)
Answer:
a) y = 0, y = 4 and y = 5
b) y ⊂ (- ∞, 0) ∪ (0, 4) ∪ (5, ∞)
c) y ⊂ (4,5)
Step-by-step explanation:
Data provided in the question:
function y(t) satisfies the differential equation:
= y⁴ − 9y³ + 20y²
Now,
a) For constant solution
= 0
or
y⁴ − 9y³ + 20y² = 0
or
y² (y² - 9y + 20 ) = 0
or
y²(y² -4y - 5y + 20) = 0
or
y²( y(y - 4) -5(y - 4)) = 0
or
y²(y - 4)(y - 5) = 0
therefore, solutions are
y = 0, y = 4 and y = 5
b) for y increasing
> 0
or
y²(y - 4)(y - 5) > 0
or
y²
y ⊂ (- ∞, 0) ∪ (0, 4) ∪ (5, ∞)
c) for y decreasing
< 0
or
y²(y - 4)(y - 5) > 0
or
y²
y ⊂ (4,5)