PreCal

Write each expression in problems 1 to 3 in the form a + bi.

1. (8-3i)+(-6+2i)
2. 4/(2-i)
3. (3-2i)^3

I do not understand at all where to start. I tired looking on google to find a way to solve but I didn't get any real help. So please help me!

  1. 👍
  2. 👎
  3. 👁
  1. 1. 8 - 6 -3i + 2i = 2 - i.

    2. 4 / (2 - i),

    Multiply numerator and denominator by 2 + i:

    (8 + 4i) / (2 - i)(2 + i),
    (8 + 4i) / (4 + 1) = (8 + 4i) / 5.

    3. (3 - 2i)^3 = (3 - 2i)^2 (3 - 2i)=
    (9 - 12i + 4) (3 - 2i),
    (13 - 12i) (3 - 2i),
    39 - 26i - 36i - 24 = 15 - 62i.

    1. 👍
    2. 👎
  2. Alright thank you. Can I also put them in my calculator? I wasn't sure but I did for the first one and got the same answer.

    1. 👍
    2. 👎
  3. That's fine if you don't have to show
    your work.

    1. 👍
    2. 👎
  4. Thank you so much for your help!

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Pre-Calc

    I am really struggling with how to do these problems, I posted them a few minutes ago but the answers/work shown was incorrect. 1) a) Use an Addition or Subtraction Formula to write the expression as a trigonometric function of

  2. Math Help? Check my answers.

    1. Name the coefficients in the polynomial. 4x^2 + 3x - 3 4, -3, -3 4, 3, 4, 3, 3, -4, -3, 2. How many terms are in the following polynomial? 6x^4 + 3x^3 - 2x^2 + 15x - 14 5 4 3 2 3. In the expression -7x - 5x^2 + 5, what is the

  3. Math

    Look at the given triangles. a. Write an expression in simplest form for the perimeter of each triangle. b. Write another expression in simplest form that shows the difference between the perimeter of the larger triangle and the

  4. algebra

    Write an expression in simplest form that represents the perimeter of the polygon. the measure of the sides are 3x, x + 10, 2x + 2, and 5x. Would the simplified expression be 11x + 12?

  1. help riemann sums

    the expression 1/50 (1/50 +2/50+ 3/50+ .....50/50)is a Reimann sum approximation for (everything in the parantheses is square root except the 1/50 outside the paratheses) the answer has to me the integral form so from looking at

  2. Algebra 2 help plsss?

    what is a simpler form of the radical expression? 4sqrt1296 x^16 y^12 how can you write the expression with rationalized denominator? 3 sqrt 2 / 3 sqrt 4 what is the quotient (4-x)/(x^2 + 5x - 6) / (x^2 - 11x + 28)/(x^2 + 7x + 6)

  3. math plz help my last chance to do this homework

    a) write an expression in simplest form for the perimeter of each triangle. b)write another expression in simplest form that shows the difference between the perimeter of the larger triangle and the perimeter of the smaller

  4. american goverment check answers

    2. Which of the following statements support the idea that free speech is essential for democracy? Select all that apply. (2 points) Free speech can be limited in times of war. Free speech advances knowledge. Free speech

  1. Math

    How to write expression by writing the solution in unit form and in standard form

  2. precalculus

    please check my answers 1.Use Gaussian elimination to write the system of equations given below in row-echelon form. 2x+4y+z=-4 2x-4y+6z=13 4x-2y+z=6 answer:2x+4y+z=-4 8y-5z=-17 z=1 2.Find the solution to the system of equations

  3. Algebra

    1.Simplify the following expression. 4(20+12)÷(4-3) 4(20+12 ÷ 1 4 32 ÷ 1 128 2.A gym membership cost $25 to join and $14 a month. Write and use an algebraic expression to find the cost of the gym membership for 6 months.

  4. math (pre calc)

    4cot^2x-4/tanx+cosxsecx write expression in factored form as an algebraic expression of a singletrig function

You can view more similar questions or ask a new question.