I think I'm missing something in this complex number problem

In summary, there is a difference between -1^{10} and (-1)^{10}, with the latter being the correct notation for raising a power. Utilizing parentheses can help to avoid confusion and ensure the correct calculation is being performed. It is important to have a strong understanding of basic mathematical principles in order to progress in more advanced topics.
  • #1
JR Sauerland
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As you can see, it says that -110 (-1 to the tenth is just -1), multiplied by i, is somehow i. Everywhere I have looked, -1 times i is negative i, but this problem disagrees. Am I missing something?
 

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  • #2
##(-1)^{10} = 1##
 
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  • #3
micromass said:
##(-1)^{10} = 1##

But how? Every calculator or form I put it into says it is -1...? EDIT: If I put -110 in my graphic calculator, it brings back -1. If I do it as (-1)10, it says 1. Witchcraft! I am so confused .:nb)
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  • #4
There is a difference between ##-1^{10}##, which is apparently what the calculators are doing and ##(-1)^{10}##.
 
  • #5
micromass said:
There is a difference between ##-1^{10}##, which is apparently what the calculators are doing and ##(-1)^{10}##.

What is the difference though?
 
  • #6
For example:

[tex](-1)^4 = (-1)\cdot (-1)\cdot (-1)\cdot (-1) = 1[/tex]

while

[tex]-1^4 = - (1\cdot 1\cdot 1\cdot 1) = -1[/tex]
 
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  • #7
micromass said:
For example:

[tex](-1)^4 = (-1)\cdot (-1)\cdot (-1)\cdot (-1) = 1[/tex]

while

[tex]-1^4 = - (1\cdot 1\cdot 1\cdot 1) = -1[/tex]

That was perfect! Thank you so much!
 
  • #8
Raising a power by convention has higher precedence over multiplication just as multiplication has a higher precedence over addition. Parentheses allow you to reorder the precedence of operations. These rules are especially good to know when you start programming.
 
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  • #9
JR you leep asking these questions that show that there are really basic things that you have not grasped. Your calculator does not give you the "right" answer because you do not know what buttons to press. If you do not know without even thinking about it that aný even power of -1 is equal to 1 then you cannot progress your studies. As you seem familiar with Khan Academy, can I suggest that you go RIGHT BACK TO THE BEGINNING and take every class?
 
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  • #10
Parentheses are your friends in programming. Use -(110) or (-1)10 to be sure what it is calculating exactly what you want it to.
 
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Related to I think I'm missing something in this complex number problem

1. What is a complex number?

A complex number is a number that contains both a real part and an imaginary part. It is represented in the form of a + bi, where a is the real part and bi is the imaginary part with the imaginary unit i equal to sqrt(-1).

2. How do I add or subtract complex numbers?

To add or subtract complex numbers, you simply add or subtract the real parts and the imaginary parts separately. For example, (3+2i) + (5+4i) = (3+5) + (2+4)i = 8 + 6i.

3. What is the conjugate of a complex number?

The conjugate of a complex number is formed by changing the sign of the imaginary part. For example, the conjugate of 3+2i is 3-2i. This is useful in dividing complex numbers.

4. How do I multiply or divide complex numbers?

To multiply complex numbers, you use the FOIL method just like with binomials. For example, (3+2i)(5+4i) = 3(5) + 3(4i) + 2i(5) + 2i(4i) = 15 + 12i + 10i + 8i^2 = 15 + 22i - 8 = 7 + 22i. To divide complex numbers, you use the conjugate of the denominator to simplify the expression.

5. What are some common applications of complex numbers?

Complex numbers have many applications in mathematics, engineering, and physics. They are used in electrical engineering for AC circuit analysis, in signal processing for analyzing waveforms, and in quantum mechanics for modeling physical systems. They are also used in graphics and animation to represent 2D and 3D objects.

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