Imaginary Numbers - Math
Card 0 of 112
Simplify the following complex number expression:

Simplify the following complex number expression:
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Begin by multiplying the numerator and denominator by the complement of the denominator:


Combine like terms:

Simplify. Remember that
is equivalent to 


Begin by multiplying the numerator and denominator by the complement of the denominator:
Combine like terms:
Simplify. Remember that is equivalent to
What is the absolute value of 
What is the absolute value of
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The absolute value is a measure of the distance of a point from the origin. Using the pythagorean distance formula to calculate this distance.
The absolute value is a measure of the distance of a point from the origin. Using the pythagorean distance formula to calculate this distance.
Simplify the expression.

Simplify the expression.
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Combine like terms. Treat
as if it were any other variable.


Substitute to eliminate
.


Simplify.

Combine like terms. Treat as if it were any other variable.
Substitute to eliminate .
Simplify.
Simplify the radical.

Simplify the radical.
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First, factor the term in the radical.


Now, we can simplify.



First, factor the term in the radical.
Now, we can simplify.
Multiply: 
Multiply:
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FOIL:






FOIL:
Multiply: 
Multiply:
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Since
and
are conmplex conjugates, they can be multiplied according to the following pattern:

Since and
are conmplex conjugates, they can be multiplied according to the following pattern:
Multiply:

Multiply:
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Since
and
are conmplex conjugates, they can be multiplied according to the following pattern:

Since and
are conmplex conjugates, they can be multiplied according to the following pattern:
Evaluate: 
Evaluate:
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can be evaluated by dividing
by 4 and noting the remainder. Since
- that is, since dividing 45 by 4 yields remainder 1:

can be evaluated by dividing
by 4 and noting the remainder. Since
- that is, since dividing 45 by 4 yields remainder 1:
Evaluate: 
Evaluate:
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Which of the following is equivalent to
?
Which of the following is equivalent to ?
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Recall the basic property of imaginary numbers,
.
Keeping this in mind,
.
Recall the basic property of imaginary numbers, .
Keeping this in mind, .
Which of the following is equivalent to:

Which of the following is equivalent to:
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Recall that
.
Then, we have that
.
Note that we used the power rule of exponents and the order of operations to simplify the exponent before multiplying by the coefficient.
Recall that .
Then, we have that .
Note that we used the power rule of exponents and the order of operations to simplify the exponent before multiplying by the coefficient.
Simplify 
Simplify
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Multiplying top and bottom by the complex conjugate
eliminates i from the denominator
Multiplying top and bottom by the complex conjugate eliminates i from the denominator
Multiply, then simplify.

Multiply, then simplify.
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Use FOIL to multiply. We can treat
as a variable for now, just as if it were an
.

Combine like terms.

Now we can substitute for
.


Simplify.

Use FOIL to multiply. We can treat as a variable for now, just as if it were an
.
Combine like terms.
Now we can substitute for .
Simplify.
Which of the following is equivalent to
, where
?
Which of the following is equivalent to , where
?
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We will need to simplify the rational expression by removing imaginary terms from the denominator. Often in such problems, we want to multiply the numerator and denominator by the conjugate of the denominator, which will usually eliminate the imaginary term from the denominator.
In this problem, the denominator is
. Remember that, in general, the conjugate of the complex number
is equal to
, where a and b are both nonzero constants. Thus, the conjugate of
is equal to
.
We need to multiply both the numerator and denominator of the fraction
by
.

Next, we use the FOIL method to simplify both the numerator and denominator. The FOIL method of binomial multiplication requires us to mutiply together the first, outside, inner, and last terms of each binomial and then sum them.

Now, we can start simplifying.

Use the fact that
.



The answer is
.
We will need to simplify the rational expression by removing imaginary terms from the denominator. Often in such problems, we want to multiply the numerator and denominator by the conjugate of the denominator, which will usually eliminate the imaginary term from the denominator.
In this problem, the denominator is . Remember that, in general, the conjugate of the complex number
is equal to
, where a and b are both nonzero constants. Thus, the conjugate of
is equal to
.
We need to multiply both the numerator and denominator of the fraction by
.
Next, we use the FOIL method to simplify both the numerator and denominator. The FOIL method of binomial multiplication requires us to mutiply together the first, outside, inner, and last terms of each binomial and then sum them.
Now, we can start simplifying.
Use the fact that .
The answer is .
Simplify the following complex number expression:

Simplify the following complex number expression:
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Begin by factoring the radical expression using imaginary numbers:


Now, multiply the factors:

Simplify. Remember that
is equivalent to 


Begin by factoring the radical expression using imaginary numbers:
Now, multiply the factors:
Simplify. Remember that is equivalent to
Simplify the following complex number expression:

Simplify the following complex number expression:
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Begin by completing the square:


Now, multiply the factors. Remember that
is equivalent to 


Begin by completing the square:
Now, multiply the factors. Remember that is equivalent to
Solvethe following complex number expression for
:

Solvethe following complex number expression for :
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Solve the equation using complex numbers:





Solve the equation using complex numbers:
Simplify the following complex number expression:

Simplify the following complex number expression:
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Begin by factoring the radical expression using imaginary numbers:


Now, multiply the factors:

Simplify. Remember that
is equivalent to 

Begin by factoring the radical expression using imaginary numbers:
Now, multiply the factors:
Simplify. Remember that is equivalent to
Simplify the following complex number expression:

Simplify the following complex number expression:
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Begin by simplifying the radicals using complex numbers:


Multiply the factors:


Simplify. Remember that
is equivalent to
.


Begin by simplifying the radicals using complex numbers:
Multiply the factors:
Simplify. Remember that is equivalent to
.
Simplify the following complex number expression:

Simplify the following complex number expression:
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Begin by completing the square:


Multiply the factors:

Simplify. Remember that
is equivalent to
.

Begin by completing the square:
Multiply the factors:
Simplify. Remember that is equivalent to
.