Solve the complex number_best way (1 Viewer)

[Richard Lee]

Qusetion:

Hi, friends! Try this question.
Find x and y is (x+iy)^2=3-4i where x and y are real number?

The best solution is posted on "The solution of complex number". I wish it will save u a lots of time and get right answer without any mistakes.

Enjoy!

 

[hyparzero]

wow, old thread, oh well....

just square the left - hand side then compare real and imaginary parts:

(x+iy)²=3 - 4i
=> x² - y² + 2iy = 3 - 4i

Thus:
x² - y² = 3 and
2iy = -4i

.'. y = -2 and x = Root(7)

 

[onebytwo]

i think you missed an x in your equating,
i think the answers are 2-i or i-2

 

[Riviet]

Yep just a silly mistake, onebytwo is correct, and nicely spotted.

 

[hyparzero]

oh no, no wonder i failed complex numbers last term

 

[Rax]

LOL, unlucky.

Mildly shotdown but eh. Complex numbers.......I can't even remember what that is anymore.
Is everyone studying up for the trials

 

[Richard Lee]

Qusetion:

Hi, friends! Try this question.
Find x and y is (x+iy)^2=3-4i where x and y are real number?

The best solution is posted on "The solution of complex number". I wish it will save u a lots of time and get right answer without any mistakes.

Enjoy!

The best solution is:

(x+iy)^2=3-4i=(2-i)^2, therefore x + iy = 2 - i or - 2 + i.
Good luck, my maths mates.

 

[hyparzero]

The best solution is:

(x+iy)^2=3-4i=(2-i)^2, therefore x + iy = 2 - i or - 2 + i.
Good luck, my maths mates.

is it just me, or is that totally stupid