Posted by Breanna on Monday, June 22, 2009 at 10:40pm.
Simplify: Write answers in the form of a + bi, where a and b are real numbers.
a. (12i)(1+3i)
b. (35i)(82i)

Algebra  bobpursley, Monday, June 22, 2009 at 10:59pm
Use FOIL to multiply them out.

Algebra  Breanna, Monday, June 22, 2009 at 11:15pm
IS this correct, i notice that i^2 = 1 what does this mean?
(12i)(1+3i)
=1+3i2i6i^2
=1+ i6i^2
= 1+i6i

Algebra  bobpursley, Monday, June 22, 2009 at 11:51pm
no, 6i^2 is 6*(1)
so the last term is +6 and the final answer is
7+i

Algebra  Breanna, Tuesday, June 23, 2009 at 12:11am
So did I do any of this correct? What do I need to fix?

Algebra  MathMate, Tuesday, June 23, 2009 at 12:56am
You have basically done it correctly, but omitted to change the sign of the last term because i^{2}=1
(12i)(1+3i)
=1+3i2i6i^2
=1+ i6i^2
= 1+i +6i

Algebra  MathMate, Tuesday, June 23, 2009 at 12:57am
Oops, it should read:
(12i)(1+3i)
=1+3i2i6i^2
=1+ i6i^2
= 1+i +6
=7+i
Answer This Question
Related Questions
 Algebra  Simplify: Write answers in the form of a + bi, where a and b are real ...
 Algebra  Simplify (4 – 5i)(3 + 7i) and write the answer in the form a + bi, ...
 Math help Ms. Sue please  1. Name the subset(s) of real numbers to which the ...
 algebra 2  1.Simplify the difference. n^2  lOn+24 9 / n^2  13n + 42 — 7 A. n...
 Algebra  Please let me know if i answered these correctly thanks 1.Which ...
 Algebra  28. Use the Distributive Property to simplify x(4x^2 + x + 4) Is it 4x...
 Algebra 1 Please, check my answers!  1. What is ((12x^6 + x)) / ((4x^2))? A...
 Algebra (need help ASAP!!!!)  I didn't get how to do the problem. In my book it...
 College Algebra~Can someone check my answers pls  f(t)=log(t5) t5>0 t>5...
 algebra  1. write an algebraic expression for the word phrase: the quotient of ...
More Related Questions