## forty-two 2 years ago simplify the expression 2-3i/1+5i

1. mathstudent55

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2. Rosy95

When i punched it into a calculator, it told me it was 2+2i

3. Raja99

in order to simplify this type of equations rationalizing the denominator allows to get a simple equation

4. mathstudent55

Here you need to get rid of i from the denominator. To do that, you need to multiply the denominator by its complex conjugate. The complex conjugate of a + bi is a - bi Since you are working with a fraction, whatever you multiply the denominator by, you must multiply the numerator by the same thing.

5. mathstudent55

The complex conjugate of 1 + 5i is 1 - 5i (1 - 5i)/(1 - 5i) = 1 becasue when you divide a number by itself (except 0) you get 1.

6. forty-two

okay so 1 -8i?

7. mathstudent55

So by multiplying your original fraction by (1 - 5i)/(1 - 5i) you are not changing the value, only the form.

8. caesar27

2+2i

9. mathstudent55

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10. mathstudent55

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11. mathstudent55

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12. forty-two

so the answer is -1/2 - 1/2i

13. mathstudent55

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14. mathstudent55

Correct

15. forty-two

thank you

16. mathstudent55

wlcm