Answer: { x | 5 < x ≤ 100 } OR { x ∈ ℝ | 5 < x ≤ 100 }
Step-by-step explanation:
{ x | 5 < x ≤ 100 }
This means:
"The set of all x's, such that x is greater than 5 and less than or equal to 100"
Another acceptable way to write this is
{ x ∈ ℝ | 5 < x ≤ 100 }
"x ∈ ℝ" simply means x is an element of all real numbers
Here is our profit as a function of # of posters
p(x) =-10x² + 200x - 250
Here is our price per poster, as a function of the # of posters:
pr(x) = 20 - x
Since we want to find the optimum price and # of posters, let's plug our price function into our profit function, to find the optimum x, and then use that to find the optimum price:
p(x) = -10 (20-x)² + 200 (20 - x) - 250
p(x) = -10 (400 -40x + x²) + 4000 - 200x - 250
Take a look at our profit function. It is a normal trinomial square, with a negative sign on the squared term. This means the curve is a downward facing parabola, so our profit maximum will be the top of the curve.
By taking the derivative, we can find where p'(x) = 0 (where the slope of p(x) equals 0), to see where the top of profit function is.
p(x) = -4000 +400x -10x² + 4000 -200x -250
p'(x) = 400 - 20x -200
0 = 200 - 20x
20x = 200
x = 10
p'(x) = 0 at x=10. This is the peak of our profit function. To find the price per poster, plug x=10 into our price function:
price = 20 - x
price = 10
Now plug x=10 into our original profit function in order to find our maximum profit:
<span>p(x)= -10x^2 +200x -250
p(x) = -10 (10)</span>² +200 (10) - 250
<span>p(x) = -1000 + 2000 - 250
p(x) = 750
Correct answer is C)</span>
Definition: <span>The square root of a number is another number, which on multiplying with itself, will give the original number.
</span>
Every positive number has two square roots. One square root is positive, while the other is exactly same, but negative. The positive square root of a number is called its principle square
root. For example, 10 and -10 are the two square roots of 100, but 10 is
called the principle square root.
Hence e<span>very positive number has two square roots , a principal square root and its opposite negative.</span>
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Answer:
8q + 6 = 8*2 + 6 = 16 + 6 = 22
