What are the Real Numbers c and d for Inverting Complex Numbers?

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SUMMARY

The discussion focuses on finding real numbers c and d that satisfy the equation \(\frac{1}{a + bi} = c + di\) for non-zero real numbers a and b. Participants confirm that by multiplying both sides by the conjugate \(a - bi\), the equation can be simplified to \(1 = (ac - bd) + (bc + ad)i\). It is established that c and d must be real numbers, as they correspond to the real and imaginary components of the equation, respectively. The conclusion emphasizes that the values of c and d can be derived directly from the properties of complex numbers.

PREREQUISITES
  • Understanding of complex numbers and their conjugates
  • Familiarity with basic algebraic manipulation
  • Knowledge of real and imaginary components of complex numbers
  • Ability to perform multiplication of complex numbers
NEXT STEPS
  • Study the properties of complex conjugates in detail
  • Learn about the geometric interpretation of complex numbers
  • Explore the concept of complex division and its applications
  • Investigate the use of complex numbers in electrical engineering
USEFUL FOR

Students studying complex numbers, mathematicians, and anyone involved in fields that utilize complex number theory, such as engineering and physics.

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Homework Statement



Suppose a and b are real numbers, not both 0. Find real numbers c and d, such that

\frac{1}{a + bi} = c + di


Homework Equations



I said that:

1 = (c + di) (a + bi)

1 = (ac - bd) + (bc + ad)i

so if b = 0 then
\frac{1}{a} = c + di

The rationale holds for if a = 0. Since this is equal to a real number 1/a can I just say that c and d are real numbers?
 
Physics news on Phys.org
You need to understand that if
x + yj = a + bj
then
x = a
and
y = b

2)
Multiply left side by a-bj / a-bj
 

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