Expanding Binomials: Simplifying Complex Expressions

In summary, the conversation is about expanding the binomial (√3/2) + (1/2)i)^4 and finding the next steps. The attempt at a solution involves incorrect assumptions and suggests using either the Binomial Theorem or expanding the binomial by its square to find the fourth power.
  • #1
killersanta
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Homework Statement



by expanding the binomial show that ( (Sqtroot(3)/2) + (1/2)i )^4 = ( (-1/2) + (sqroot(3)/2)i )



The Attempt at a Solution



I'm stuck, I now ( (Sqtroot(3)/2) + (1/2)i )^4 = ( (9/16) + (1/16)i )

But that's all I got, don't know the next steps.
 
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  • #2
killersanta said:

Homework Statement



by expanding the binomial show that ( (Sqtroot(3)/2) + (1/2)i )^4 = ( (-1/2) + (sqroot(3)/2)i )



The Attempt at a Solution



I'm stuck, I now ( (Sqtroot(3)/2) + (1/2)i )^4 = ( (9/16) + (1/16)i )

But that's all I got, don't know the next steps.

It looks like you are saying that (a + b)4 = a4 + b4. Or that (a + bi)4 = a4 + b4i. Neither is true at all. If you know about the Binomial Theorem you can get the coefficients. For example, (a + b)4 = a4 + 4a3b + 6a2b2 + 4ab3 + b4.

If you don't know about that theorem you can just expand the left side by the square of that binomial, and then multiplying the result by itself. That will give you the fourth power of your binomial.
 
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FAQ: Expanding Binomials: Simplifying Complex Expressions

What is the binomial theorem?

The binomial theorem is a mathematical formula used to expand an expression with two terms raised to a power. It is used to simplify and solve equations involving binomials.

How do you expand a binomial?

To expand a binomial, you can use the binomial theorem or the FOIL method. The binomial theorem involves using a formula to find the coefficients of each term in the expansion, while the FOIL method involves multiplying each term in the first binomial by each term in the second binomial.

What is the purpose of expanding a binomial?

Expanding a binomial allows us to simplify and solve equations involving binomials. It also helps us to find the coefficients of each term in the expansion, which can be useful in other mathematical calculations.

What are the common mistakes made when expanding a binomial?

One common mistake is forgetting to apply the exponent to each term in the binomial. Another mistake is not distributing the coefficients properly when using the FOIL method. It is also important to pay attention to the signs in front of each term to avoid making errors.

Can the binomial theorem be used for any power?

Yes, the binomial theorem can be used for any power, including whole numbers, fractions, and negative numbers. However, it may become more complex for higher powers and may require more steps to expand the binomial.

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