1.5E: Exercises
- Page ID
- 120108
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Exercises
In Exercises 1 - 10, use the pair of functions \(\ f\) and \(\ g\) to find the following values if they exist.
- \(\ (f + g)(2)\)
- \(\ (f − g)(−1) \)
- \(\ (g − f)(1)\)
- \(\ (f g)\left(\frac{1}{2}\right)\)
- \(\ \left(\frac{f}{g}\right)(0)\)
- \(\ \left(\frac{g}{f}\right)(-2)\)
- \(\ f(x) = 3x + 1\) and \(\ g(x) = 4 − x\)
- \(\ f(x)=x^{2}\) and \(\ g(x) = −2x + 1\)
- \(\ f(x)=x^{2}-x\) and \(\ g(x)=12-x^{2}\)
- \(\ f(x)=2 x^{3}\) and \(\ g(x)=-x^{2}-2 x-3\)
- \(\ f(x)=\sqrt{x+3}\) and \(\ g(x) = 2x − 1\)
- \(\ f(x)=\sqrt{4-x}\) and \(\ g(x)=\sqrt{x+2}\)
- \(\ f(x)=2 x\) and \(\ g(x)=\frac{1}{2 x+1}\)
- \(\ f(x)=x^{2}\) and \(\ g(x)=\frac{3}{2 x-3}\)
- \(\ f(x)=x^{2}\) and \(\ g(x)=\frac{1}{x^{2}}\)
- \(\ f(x)=x^{2}+1\) and \(\ g(x)=\frac{1}{x^{2}+1}\)
In Exercises 11 - 20, use the pair of functions \(\ f\) and \(\ g\) to find the domain of the indicated function then find and simplify an expression for it.
- \(\ (f + g)(x)\)
- \(\ (f − g)(x)\)
- \(\ (fg)(x)\)
- \(\ \left(\frac{f}{g}\right)(x)\)
- \(\ f(x) = 2x + 1\) and \(\ g(x) = x − 2\)
- \(\ f(x) = 1 − 4x\) and \(\ g(x) = 2x − 1\)
- \(\ f(x)=x^{2}\) and \(\ g(x) = 3x − 1\)
- \(\ f(x)=x^{2}-x\) and \(\ g(x) = 7x\)
- \(\ f(x)=x^{2}-4\) and \(\ g(x) = 3x + 6\)
- \(\ f(x)=-x^{2}+x+6\) and \(\ g(x)=x^{2}-9\)
- \(\ f(x)=\frac{x}{2}\) and \(\ g(x)=\frac{2}{x}\)
- \(\ f(x) = x − 1\) and \(\ g(x)=\frac{1}{x-1}\)
- \(\ f(x) = x\) and \(\ g(x)=\sqrt{x+1}\)
- \(\ f(x)=\sqrt{x-5}\) and \(\ g(x)=f(x)=\sqrt{x-5}\)
In Exercises 21 - 45, find and simplify the difference quotient \(\ \frac{f(x+h)-f(x)}{h}\) for the given function.
- \(\ f(x) = 2x − 5\)
- [MOM] \(\ f(x) = −3x + 5\)
- [MOM] \(\ f(x) = 6\)
- [MOM] \(\ f(x)=3 x^{2}-x\)
- [MOM] \(\ f(x)=-x^{2}+2 x-1\)
- \(\ f(x)=4 x^{2}\)
- \(\ f(x)=x-x^{2}\)
- \(\ f(x)=x^{3}+1\)
- \(\ f(x) = mx + b\) where \(\ m \neq 0\)
- \(\ f(x)=a x^{2}+b x+c\) where \(\ a \neq 0\)
- \(\ f(x)=\frac{2}{x}\)
- [MOM] \(\ f(x)=\frac{3}{1-x}\)
- \(\ f(x)=\frac{1}{x^{2}}\)
- [MOM] \(\ f(x)=\frac{2}{x+5}\)
- \(\ f(x)=\frac{1}{4 x-3}\)
- [MOM] \(\ f(x)=\frac{3 x}{x+1}\)
- \(\ f(x)=\frac{x}{x-9}\)
- \(\ f(x)=\frac{x^{2}}{2 x+1}\)
- [MOM] \(\ f(x)=\sqrt{x-9}\)
- \(\ f(x)=\sqrt{2 x+1}\)
- \(\ f(x)=\sqrt{-4 x+5}\)
- \(\ f(x)=\sqrt{4-x}\)
- \(\ f(x)=\sqrt{a x+b}\), where \(\ a \neq 0\).
- \(\ f(x)=x \sqrt{x}\)
- \(\ f(x)=\sqrt[3]{x}\). HINT: \(\ (a-b)\left(a^{2}+a b+b^{2}\right)=a^{3}-b^{3}\)
In Exercises 46 - 50, \(\ C(x)\) denotes the cost to produce \(\ x\) items and \(\ p(x)\) denotes the price-demand function in the given economic scenario. In each Exercise, do the following
- Find and interpret \(\ C(0)\).
- Find and interpret \(\ \overline{C}(10)\).
- Find and interpret \(\ p(5)\).
- Find and simplify \(\ R(x)\).
- Find and simplify \(\ P(x)\).
- Solve \(\ P(x) = 0\) and interpret.
- The cost, in dollars, to produce \(\ x\) “I’d rather be a Sasquatch” T-Shirts is \(\ C(x) = 2x + 26\), \(\ x ≥ 0\) and the price-demand function, in dollars per shirt, is \(\ p(x) = 30 − 2x\), \(\ 0 ≤ x ≤ 15\).
- The cost, in dollars, to produce \(\ x\) bottles of 100% All-Natural Certified Free-Trade Organic Sasquatch Tonic is \(\ C(x) = 10x + 100\), \(\ x ≥ 0\) and the price-demand function, in dollars per bottle, is \(\ p(x) = 35 − x, 0 ≤ x ≤ 35\).
- The cost, in cents, to produce x cups of Mountain Thunder Lemonade at Junior’s Lemonade Stand is \(\ C(x) = 18x + 240\), \(\ x ≥ 0\) and the price-demand function, in cents per cup, is \(\ p(x) = 90 − 3x, 0 ≤ x ≤ 30\).
- The daily cost, in dollars, to produce \(\ x\) Sasquatch Berry Pies \(\ C(x) = 3x + 36\), \(\ x ≥ 0\) and the price-demand function, in dollars per pie, is \(\ p(x) = 12 − 0.5x\), \(\ 0 ≤ x ≤ 24\).
- The monthly cost, in hundreds of dollars, to produce x custom built electric scooters is \(\ C(x) = 20x + 1000\), \(\ x ≥ 0\) and the price-demand function, in hundreds of dollars per scooter, is \(\ p(x) = 140 − 2x\), \(\ 0 ≤ x ≤ 70\).
In Exercises 51 - 62, let f be the function defined by
\(\ f=\{(-3,4),(-2,2),(-1,0),(0,1),(1,3),(2,4),(3,-1)\}\)
and let \(\ g\) be the function defined
\(\ g=\{(-3,-2),(-2,0),(-1,-4),(0,0),(1,-3),(2,1),(3,2)\}\)
Compute the indicated value if it exists.
- \(\ (f + g)(−3)\)
- \(\ (f − g)(2)\)
- \(\ (fg)(−1)\)
- \(\ (g + f)(1)\)
- \(\ (g − f)(3)\)
- \(\ (gf)(−3)\)
- \(\ \left(\frac{f}{g}\right)(-2)\)
- \(\ \left(\frac{f}{g}\right)(-1)\)
- \(\ \left(\frac{f}{g}\right)(2)\)
- \(\ \left(\frac{g}{f}\right)(-1)\)
- \(\ \left(\frac{g}{f}\right)(3)\)
- \(\ \left(\frac{g}{f}\right)(-3)\)
Answers
- For \(\ f(x) = 3x + 1\) and \(\ g(x) = 4 − x\)
- \(\ (f + g)(2) = 9\)
- \(\ (f − g)(−1) = −7\)
- \(\ (g − f)(1) = −1\)
- \(\ (f g)\left(\frac{1}{2}\right)=\frac{35}{4}\)
- \(\ \left(\frac{f}{g}\right)(0)=\frac{1}{4}\)
- \(\ \left(\frac{g}{f}\right)(-2)=-\frac{6}{5}\)
- For \(\ f(x)=x^{2}\) and \(\ g(x)=-2 x+1\)
- \(\ (f + g)(2) = 1\)
- \(\ (f − g)(−1) = − 2\)
- \(\ (g − f)(1) = − 2\)
- \(\ (f g)\left(\frac{1}{2}\right)=0\)
- \(\ \left(\frac{f}{g}\right)(0)=0\)
- \(\ \left(\frac{g}{f}\right)(-2)=\frac{5}{4}\)
- For \(\ f(x)=x^{2}-x\) and \(\ g(x)=12-x^{2}\)
- \(\ (f + g)(2) = 10\)
- \(\ (f − g)(−1) = − 9\)
- \(\ (g − f)(1) = 11\)
- \(\ (f g)\left(\frac{1}{2}\right)=-\frac{47}{16}\)
- \(\ \left(\frac{f}{g}\right)(0)=0\)
- \(\ \left(\frac{g}{f}\right)(-2)=\frac{4}{3}\)
- For \(\ f(x)=2 x^{3}\) and \(\ g(x)=-x^{2}-2 x-3\)
- \(\ (f + g)(2) = 5\)
- \(\ (f − g)(−1) = 0\)
- \(\ (g − f)(1) = − 8\)
- \(\ (f g)\left(\frac{1}{2}\right)=-\frac{17}{16}\)
- \(\ \left(\frac{f}{g}\right)(0)=0\)
- \(\ \left(\frac{g}{f}\right)(-2)=\frac{3}{16}\)
- For \(\ f(x)=\sqrt{x+3}\) and \(\ g(x) = 2x - 1\)
- \(\ (f+g)(2)=3+\sqrt{5}\)
- \(\ (f-g)(-1)=3+\sqrt{2}\)
- \(\ (g − f)(1) = -1\)
- \(\ (f g)\left(\frac{1}{2}\right)=0\)
- \(\ \left(\frac{f}{g}\right)(0)=-\sqrt{3}\)
- \(\ \left(\frac{g}{f}\right)(-2)=-5\)
- For \(\ f(x)=\sqrt{4-x}\) and \(\ g(x)=\sqrt{x+2}\)
- \(\ (f+g)(2)=2+\sqrt{2}\)
- \(\ (f-g)(-1)=-1+\sqrt{5}\)
- \(\ (g − f)(1) = 0\)
- \(\ (f g)\left(\frac{1}{2}\right)=\frac{\sqrt{35}}{2}\)
- \(\ \left(\frac{f}{g}\right)(0)=\sqrt{2}\)
- \(\ \left(\frac{g}{f}\right)(-2)=0\)
- For \(\ f(x) = 2x\) and \(\ g(x)=\frac{1}{2 x+1}\)
- \(\ (f+g)(2)=\frac{21}{5}\)
- \(\ (f − g)(−1) = −1\)
- \(\ (g-f)(1)=-\frac{5}{3}\)
- \(\ (f g)\left(\frac{1}{2}\right)=\frac{1}{2}\)
- \(\ \left(\frac{f}{g}\right)(0)=0\)
- \(\ \left(\frac{g}{f}\right)(-2)=\frac{1}{12}\)
- For \(\ f(x)=x^{2}\) and \(\ g(x)=\frac{3}{2 x-3}\)
- \(\ (f + g)(2) = 7\)
- \(\ (f-g)(-1)=\frac{8}{5}\)
- \(\ (g − f)(1) = −4\)
- \(\ (f g)\left(\frac{1}{2}\right)=-\frac{3}{8}\)
- \(\ \left(\frac{f}{g}\right)(0)=0\)
- \(\ \left(\frac{g}{f}\right)(-2)=-\frac{3}{28}\)
- For \(\ f(x)=x^{2}\) and \(\ g(x)=\frac{1}{x^{2}}\)
- \(\ (f+g)(2)=\frac{17}{4}\)
- \(\ (f − g)(−1) = 0\)
- \(\ (g − f)(1) = 0\)
- \(\ (f g)\left(\frac{1}{2}\right)=1\)
- \(\ \left(\frac{f}{g}\right)(0)\) is undefined.
- \(\ \left(\frac{g}{f}\right)(-2)=\frac{1}{16}\)
- For \(\ f(x)=x^{2}+1\) and \(\ g(x)=\frac{1}{x^{2}+1}\)
- \(\ (f+g)(2)=\frac{26}{5}\)
- \(\ (f-g)(-1)=\frac{3}{2}\)
- \(\ (g-f)(1)=-\frac{3}{2}\)
- \(\ (f g)\left(\frac{1}{2}\right)=1\)
- \(\ \left(\frac{f}{g}\right)(0)=1\)
- \(\ \left(\frac{g}{f}\right)(-2)=\frac{1}{25}\)
- For For \(\ f(x) = 2x + 1\) and \(\ g(x) = x - 2\)
- \(\ (f + g)(x) = 3x - 1\)
Domain: \(\ (-\infty, \infty)\)
- ˆ\(\ (f − g)(x) = x + 3\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f g)(x)=2 x^{2}-3 x-2\)
Domain: \(\ (-\infty, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=\frac{2 x+1}{x-2}\)
Domain: \(\ (-\infty, 2) \cup(2, \infty)\)
- \(\ (f + g)(x) = 3x - 1\)
- For \(\ f(x) = 1 − 4x\) and \(\ g(x) = 2x - 1\)
- ˆ (f + g)(x) = -2x
Domain: \(\ (-\infty, \infty)\)
- ˆ \(\ (f − g)(x) = 2 - 6x\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f g)(x)=-8 x^{2}+6 x-1\)
Domain: \(\ (-\infty, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=\frac{1-4 x}{2 x-1}\)
Domain: \(\ \left(-\infty, \frac{1}{2}\right) \cup\left(\frac{1}{2}, \infty\right)\)
- ˆ (f + g)(x) = -2x
- For \(\ f(x)=x^{2}\) and \(\ g(x) = 3x − 1\)
- \(\ (f+g)(x)=x^{2}+3 x-1\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f-g)(x)=x^{2}-3 x+1\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f g)(x)=3 x^{3}-x^{2}\)
Domain: \(\ (-\infty, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=\frac{x^{2}}{3 x-1}\)
Domain: \(\ \left(-\infty, \frac{1}{3}\right) \cup\left(\frac{1}{3}, \infty\right)\)
- \(\ (f+g)(x)=x^{2}+3 x-1\)
- For \(\ f(x)=x^{2}-x\) and \(\ g(x) = 7x\)
- \(\ (f+g)(x)=x^{2}+6 x\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f-g)(x)=x^{2}-8 x\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f g)(x)=7 x^{3}-7 x^{2}\)
Domain: \(\ (-\infty, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=\frac{x-1}{7}\)
Domain: \(\ (-\infty, 0) \cup(0, \infty)\)
- \(\ (f+g)(x)=x^{2}+6 x\)
- For \(\ f(x)=x^{2}-4\) and \(\ g(x) = 3x + 6\)
- \(\ (f+g)(x)=x^{2}+3 x+2\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f-g)(x)=x^{2}-3 x-10\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f g)(x)=3 x^{3}+6 x^{2}-12 x-24\)
Domain: \(\ (-\infty, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=\frac{x-2}{3}\)
Domain: \(\ (-\infty,-2) \cup(-2, \infty)\)
- \(\ (f+g)(x)=x^{2}+3 x+2\)
- For \(\ f(x)=-x^{2}+x+6\) and \(\ g(x)=x^{2}-9\)
- ˆ\(\ (f + g)(x) = x − 3\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f-g)(x)=-2 x^{2}+x+15\)
Domain: \(\ (-\infty, \infty)\)
- \(\ (f g)(x)=-x^{4}+x^{3}+15 x^{2}-9 x-54\)
Domain: \(\ (-\infty, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=-\frac{x+2}{x+3}\)
Domain: \(\ (-\infty,-3) \cup(-3,3) \cup(3, \infty)\)
- ˆ\(\ (f + g)(x) = x − 3\)
- For \(\ f(x)=\frac{x}{2}\) and \(\ g(x)=\frac{2}{x}\)
- \(\ (f+g)(x)=\frac{x^{2}+4}{2 x}\)
Domain: \(\ (-\infty, 0) \cup(0, \infty)\)
- \(\ (f-g)(x)=\frac{x^{2}-4}{2 x}\)
Domain: \(\ (-\infty, 0) \cup(0, \infty)\)
- ˆ\(\ (fg)(x) = 1\)
Domain: \(\ (-\infty, 0) \cup(0, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=\frac{x^{2}}{4}\)
Domain: \(\ (-\infty, 0) \cup(0, \infty)\)
- \(\ (f+g)(x)=\frac{x^{2}+4}{2 x}\)
- For \(\ f(x) = x − 1\) and \(\ g(x)=\frac{1}{x-1}\)
- \(\ (f+g)(x)=\frac{x^{2}-2 x+2}{x-1}\)
Domain: \(\ (-\infty, 1) \cup(1, \infty)\)
- \(\ (f-g)(x)=\frac{x^{2}-2 x}{x-1}\)
Domain: \(\ (-\infty, 1) \cup(1, \infty)\)
- \(\ (fg)(x) = 1\)
Domain: \(\ (-\infty, 1) \cup(1, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=x^{2}-2 x+1\)
Domain: \(\ (-\infty, 1) \cup(1, \infty)\)
- \(\ (f+g)(x)=\frac{x^{2}-2 x+2}{x-1}\)
- For \(\ f(x) = x\) and \(\ g(x)=\sqrt{x+1}\)
- \(\ (f+g)(x)=x+\sqrt{x+1}\)
Domain: \(\ [-1, \infty)\)
- \(\ (f-g)(x)=x-\sqrt{x+1}\)
Domain: \(\ [-1, \infty)\)
- \(\ (f g)(x)=x \sqrt{x+1}\)
Domain: \(\ [-1, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=\frac{x}{\sqrt{x+1}}\)
Domain: \(\ (-1, \infty)\)
- \(\ (f+g)(x)=x+\sqrt{x+1}\)
- For \(\ f(x)=\sqrt{x-5}\) and \(\ g(x)=f(x)=\sqrt{x-5}\)
- \(\ (f+g)(x)=2 \sqrt{x-5}\)
Domain: \(\ [5, \infty)\)
- (f − g)(x) = 0
Domain: \(\ [5, \infty)\)
- \(\ (fg)(x) = x − 5\)
Domain: \(\ [5, \infty)\)
- \(\ \left(\frac{f}{g}\right)(x)=1\)
Domain: \(\ (5, \infty)\)
- \(\ (f+g)(x)=2 \sqrt{x-5}\)
- 2
- [MOM]
- [MOM]
- [MOM]
- [MOM]
- \(\ 8x + 4h\)
- \(\ −2x − h + 1\)
- \(\ 3 x^{2}+3 x h+h^{2}\)
- \(\ m\)
- \(\ 2ax + ah + b\)
- \(\ \frac{-2}{x(x+h)}\)
- [MOM]
- \(\ \frac{-(2 x+h)}{x^{2}(x+h)^{2}}\)
- [MOM]
- \(\ \frac{-4}{(4 x-3)(4 x+4 h-3)}\)
- [MOM]
- \(\ \frac{-9}{(x-9)(x+h-9)}\)
- \(\ \frac{2 x^{2}+2 x h+2 x+h}{(2 x+1)(2 x+2 h+1)}\)
- [MOM]
- \(\ \frac{2}{\sqrt{2 x+2 h+1}+\sqrt{2 x+1}}\)
- \(\ \frac{-4}{\sqrt{-4 x-4 h+5}+\sqrt{-4 x+5}}\)
- \(\ \frac{-1}{\sqrt{4-x-h}+\sqrt{4-x}}\)
- \(\ \frac{a}{\sqrt{a x+a h+b}+\sqrt{a x+b}}\)
- \(\ \frac{3 x^{2}+3 x h+h^{2}}{(x+h)^{3 / 2}+x^{3 / 2}}\)
- \(\ \frac{1}{(x+h)^{2 / 3}+(x+h)^{1 / 3} x^{1 / 3}+x^{2 / 3}}\)
-
- \(\ C(0)=26\), so the fixed costs are $26.
- \(\ \overline{C}(10)=4.6\), so when 10 shirts are produced, the cost per shirt is $4.60.
- \(\ p(5) = 20\), so to sell 5 shirts, set the price at $20 per shirt.
- \(\ R(x)=-2 x^{2}+30 x\), \(\ 0 ≤ x ≤ 15\)
- \(\ P(x)=-2 x^{2}+28 x-26\), \(\ 0 ≤ x ≤ 15\)
- \(\ P(x) = 0\) when \(\ x = 1\) and \(\ x = 13\). These are the ‘break even’ points, so selling 1 shirt or 13 shirts will guarantee the revenue earned exactly recoups the cost of production.
-
- \(\ C(0)=100\), so the fixed costs are $100.
- \(\ \overline{C}(10)=20\), so when 10 bottles of tonic are produced, the cost per bottle is $20.
- \(\ p(5) = 30\), so to sell 5 bottles of tonic, set the price at $30 per bottle.
- \(\ R(x)=-x^{2}+35 x, 0 \leq x \leq 35\)
- \(\ P(x)=-x^{2}+25 x-100,0 \leq x \leq 35\)
- \(\ P(x)=0\), when \(\ x = 5\) and \(\ x = 20\). These are the ‘break even’ points, so selling 5 bottles of tonic or 20 bottles of tonic will guarantee the revenue earned exactly recoups the cost of production.
-
- \(\ C(0)=240\), so the fixed costs are 240¢ or $2.40.
- \(\ \overline{C}(10)=42\), so when 10 cups of lemonade are made, the cost per cup is 42¢.
- \(\ p(5) = 75\), so to sell 5 cups of lemonade, set the price at 75¢ per cup.
- \(\ R(x)=-3 x^{2}+90 x, 0 \leq x \leq 30\)
- \(\ P(x)=-3 x^{2}+72 x-240,0 \leq x \leq 30\)
- \(\ P(x) = 0\) when \(\ x = 4\) and \(\ x = 20\). These are the ‘break even’ points, so selling 4 cups of lemonade or 20 cups of lemonade will guarantee the revenue earned exactly recoups the cost of production.
-
- \(\ C(0) = 36\), so the daily fixed costs are $36.
- \(\ \overline{C}(10)=6.6\), so when 10 pies are made, the cost per pie is $6.60.
- \(\ p(5) = 9.5\), so to sell 5 pies a day, set the price at $9.50 per pie.
- \(\ R(x)=-0.5 x^{2}+12 x, 0 \leq x \leq 24\)
- \(\ P(x)=-0.5 x^{2}+9 x-36,0 \leq x \leq 24\)
- \(\ P(x) = 0\) when \(\ x = 6\) and \(\ x = 12\). These are the ‘break even’ points, so selling 6 pies or 12 pies a day will guarantee the revenue earned exactly recoups the cost of production.
-
- \(\ C(0) = 1000\), so the monthly fixed costs are 1000 hundred dollars, or $100,000.
- \(\ \overline{C}(10)=120\), so when 10 scooters are made, the cost per scooter is 120 hundred dollars, or $12,000.
- \(\ p(5) = 130\), so to sell 5 scooters a month, set the price at 130 hundred dollars, or $13,000 per scooter.
- \(\ R(x)=-2 x^{2}+140 x, 0 \leq x \leq 70\)
- \(\ P(x)=-2 x^{2}+120 x-1000,0 \leq x \leq 70\)
- P(x) = 0 when x = 10 and x = 50. These are the ‘break even’ points, so selling 10 scooters or 50 scooters a month will guarantee the revenue earned exactly recoups the cost of production.
- \(\ (f + g)(−3) = 2\)
- \(\ (f − g)(2) = 3\)
- \(\ (fg)(−1) = 0\)
- \(\ (g + f)(1) = 0\)
- \(\ (g − f)(3) = 3\)
- \(\ (gf)(−3) = −8\)
- \(\ \left(\frac{f}{g}\right)(-2)\) does not exist
- \(\ \left(\frac{f}{g}\right)(-1)=0\)
- \(\ \left(\frac{f}{g}\right)(2)=4\)
- \(\ \left(\frac{g}{f}\right)(-1)\) does not exist
- \(\ \left(\frac{g}{f}\right)(3)=-2\)
- \(\ \left(\frac{g}{f}\right)(-3)=-\frac{1}{2}\)