Practice Test 64 - Algebra 2

20 questions. Answer them in any order, then submit to see your score and every explanation.

  1. When a divisor is (x−c)(x-c), synthetic division is a streamlined alternative to long division: list coefficients (use 00 if needed), then bring down, multiply by cc, and add. Use synthetic division to divide P(x)=x4−2x3+0x2+5x−1P(x)=x^4-2x^3+0x^2+5x-1 by (x+1)=(x−(−1))(x+1)=(x-(-1)) (so c=−1c=-1). What are the quotient and remainder (remainder =P(−1)=P(-1))?
  2. Graph f(x)=x(x−4)(x+1)2f(x)=x(x-4)(x+1)^2 showing all zeros, whether the graph crosses or touches at each zero, and the end behavior.
  3. A medication dose starts at 120 mg in the bloodstream. Each hour, 25%25\% of the medication is eliminated. Create an exponential decay model for the amount M(t)M(t) after tt hours, then solve for when the amount drops to 30 mg. Round to the nearest tenth of an hour and interpret your result.
  4. A ball is dropped from 1010 ft and each bounce reaches 80%80\% of the previous height. What is the total vertical distance traveled during the first 5 bounces (up and down), not including the initial drop? Distance for bounce kk is 2(10)(0.8k)2(10)(0.8^k) for k=1,2,3,4,5k=1,2,3,4,5.
  5. Multiply and write the result in standard form (polynomials are closed under multiplication): (x2−3x+2)(x+4)(x^2 - 3x + 2)(x + 4)
  6. A roller coaster's height above ground (in meters) is modeled on the interval 0≤x≤60\le x\le 6 by the function H(x)=−x2+6x+1H(x)=-x^2+6x+1, where xx is horizontal distance (in tens of meters). What is the absolute maximum of HH on [0,6][0,6] (give the point)?
  7. A physics student is studying the relationship between the height hh of a pendulum's release point and its period TT. The data suggests the relationship T=khT = k\sqrt{h} where kk is a constant. If T=2T = 2 seconds when h=16h = 16 feet, which statement about graphing this relationship is correct?
  8. Predict the solution type using the discriminant, then solve in a±bia\pm bi form: x2−6x+10=0x^2 - 6x + 10 = 0.
  9. Determine whether the data are best modeled by a linear or exponential function, and write a function that models the data. Table: x:0, 1, 2, 3x: 0,\ 1,\ 2,\ 3 and f(x):18, 15, 12, 9f(x): 18,\ 15,\ 12,\ 9
  10. A rectangular garden has a perimeter of 48 feet. Let ll be the length (ft) and ww be the width (ft). Write an equation relating ll and ww, and choose appropriate axes labels and a reasonable scale to graph the relationship in the first quadrant.
  11. A number and its reciprocal have a sum of 103\frac{10}{3}. Write and solve an equation to find the number. Let xx = the number (assume x≠0x\ne 0).
  12. A ride-sharing company models driver earnings (in dollars) after xx hours by E(x)=∣x−5∣−2E(x)=|x-5|-2. Identify the x-intercept(s) of EE (as points).
  13. What is the horizontal asymptote of the exponential function p(x)=2ex+4p(x)=2e^{x}+4?​
  14. In chemistry, the ideal gas law is PV=nRTPV = nRT, where PP is pressure, VV is volume, nn is number of moles, RR is a constant, and TT is temperature. Solve PV=nRTPV = nRT for TT.
  15. Solve x2−7x+10=0x^2 - 7x + 10 = 0 by factoring or by the quadratic formula. Which pair of solutions is correct?​
  16. Solve the equation 8⋅et/3=908\cdot e^{t/3}=90 for tt. Give the exact answer as a logarithm and then approximate using technology.
  17. For the sequence 14, 10, 6, 2, …14,\ 10,\ 6,\ 2,\ \dots, write both a recursive formula and an explicit formula for ana_n (with n≥1n\ge 1).
  18. Show by composition that f(x)=x3+2f(x)=x^3+2 and g(x)=x−23g(x)=\sqrt[3]{x-2} are inverse functions. Compute f(g(x))f(g(x)) and g(f(x))g(f(x)) and check whether both simplify to xx.
  19. Rewrite the exponential equation 103=100010^3 = 1000 in logarithmic form.​
  20. The function f(x)=(x+1)2−5f(x)=(x+1)^2-5 is not one-to-one on all real numbers because it fails the horizontal line test. What is a suitable domain restriction that makes ff invertible?​

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