# Math Is Fun Forum

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## #1 2023-11-21 03:52:35

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Complex Numbers

Write the expression in the standard form a + bi.

6i^3 + 4i^5

6(-i) + 4(i)

-6i + 4i

My answer = -2i

Textbook answer = -10i

Why is my answer wrong?

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## #2 2023-11-21 06:20:55

Bob
Registered: 2010-06-20
Posts: 10,546

### Re: Complex Numbers

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #3 2023-11-21 07:12:36

amnkb
Member
Registered: 2023-09-19
Posts: 253

### Re: Complex Numbers

sologuitar wrote:

Write the expression in the standard form a + bi.

6i^3 + 4i^5

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## #4 2023-11-22 10:36:04

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Re: Complex Numbers

Bob wrote:

Bob

Thanks. It must be a textbook typo. Math and physics books are famous for having lots of computational errors.

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## #5 2023-11-22 10:37:13

sologuitar
Member
Registered: 2022-09-19
Posts: 467

### Re: Complex Numbers

amnkb wrote:
sologuitar wrote:

Write the expression in the standard form a + bi.

6i^3 + 4i^5

Sure feels good to be right. Like I told Bob, math and physics books are famous for having computational errors.

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