SOLUTION: Perform the indicated operations. (6-7i)(8-i) Please give a straight answer.

Algebra ->  Complex Numbers Imaginary Numbers Solvers and Lesson -> SOLUTION: Perform the indicated operations. (6-7i)(8-i) Please give a straight answer.       Log On


   

Question 1066827: Perform the indicated operations.
(6-7i)(8-i)
Please give a straight answer.
Found 2 solutions by math_helper, ikleyn:
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
Perform the indicated operations.
(6-7i)(8-i)
Please give a straight answer.
—
%286-7i%29%288-i%29++ =
+48-6i-56i%2B7i%5E2++ =
Combining -6i - 56i and recalling that i*i = -1
++48+-+62i+%2B+%287%29%28-1%29+ =
+highlight%28+41+-+62i+%29+
—
I encourage you to practice these as they will become very easy for you if you practice.

Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
.
Perform the indicated operations.
(6-7i)(8-i)
Please give a straight answer.
~~~~~~~~~~~~~~~~~~~~~~~~~

(6-7i)*(8-i) = 6*8 -7*8*i - 6*i + 7*(i^2) = (48-7) - 56i - 6i = 41 - 62i.

Answer. 41 -62i.


See the lessons on complex numbers
    - Complex numbers and arithmetical operations on them
    - Complex plane
    - Addition and subtraction of complex numbers in complex plane
    - Multiplication and division of complex numbers in complex plane

    - Solved problems on arithmetic operations on complex numbers
in this site.

Also, you have this free of charge online textbook in ALGEBRA-II in this site
    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic "Complex numbers".