math

Is 2+i a solution of z^2-4z+5=0? Please help!!!!!!! :(

  1. 2
asked by Andrea
  1. z^2 - 4z + 5 = 0

    (Note that the square of i is equal to -1)

    (2 + i)^2 - 4(2 + i) + 5
    = 4 + (i^2) + 4i - 8 - 4i + 5
    = 4 - 1 - 8 + 5
    = 9 - 9
    = 0

    Hence, yes, it is a solution.

    posted by Arora

Respond to this Question

First Name

Your Response

Similar Questions

  1. science

    1. Which of the following is TRUE regarding this situation: Solution A has a pH of 7.38, and Solution B has a pH of 7.42? a.Solution B is more acidic than Solution A b.The pH of Solution A falls within the homeostatic pH range for
  2. Pre Calculus

    a biologist has three salt solutions: some 5% solution, some 15% solution, and some 25% solution. She needs to mix some of each to get 50 liters of 20% solution. She wants to use twice as much of the 5% solution as the 15%
  3. Math Algebra , high school

    A biologist has three salt solutions: some 5% solution, some 15% solution, and some 25% solution. She needs to mix some of each to get 50 liters of 20% solution. She wants to us twice as much of the 5% solution as the 15%
  4. Science

    5. You have made the following two solutions: X) hydrogen ion concentration = 1 x 10-5M Y) pH = 4 State which statements below are true and which are false: a. Solution X contains 1 x 10-9M hydroxide ions. b. Solution X contains
  5. Chemistry 2 - pH

    You are given an aqueous salt solution and have determined that its pH is 5.19 at 25°C. Predict which of the following three salt solutions it is most likely to be. solution (1): a solution of ammonium nitrate (NH4NO3) solution
  6. Chemistry

    Captain Kirk, of the Starship Enterprise, has been told by his superiors that only a chemist can be trusted with the combination to the safe containing the dilithium crystals that power the ship. The combination is the pH of
  7. ALGEBRA CHECK ANSWERS

    Solve each equation by graphing the related function. If the equation has no real-number solution, write no solution. NOTE: when I write + it has a minus on the bottom too x^2+7=0 a. x= +7 b. x = +3.5 c. x= 0 d. no solution ***
  8. Math. Check my answers

    1. What is the solution to 89+k=-42? a. K = 131 b. K = 47 c. K = -47 d. K = -131** 2. What is the additive inverse of -7? a. -7 b. 7** c. -|-7| d. -(-(-7)) 3. What is the solution to y-7=-7? a. y=14 b. y=7 c. y=0** d. y=-7 4. What
  9. Chemistry

    What is the molarity of a solution of Mg(OH)2 if the solution contains 1.35 g in exactly 100 mL of solution??? A 15.0 mL solution of H2SO3 is neutralized by 12.0 mL of a standradized 1.00M NaOH solution. What is the concentration
  10. Chemistry

    If 50.0 mL of a 1.00 M solution of CaCl2 (solution A) is mixed with 85.0 mL of pure water to produce solution B and then 42.5 mL of solution B is mixed with 52.0 mL of solution A to give solution C, what is the concentration of
  11. Chemistry

    A teacher prepares a saturated NaCli solution at 55 Degree C. What is the % by mass 9m/m0 of this solution? what is the concentration of this solution expressed in ppm? What is the molality of this solution? If the density of the

More Similar Questions