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How do you find the absolute value of |5-i|?

Answer 1

Theodore Amidon

#sqrt26#

#"given the complex number "z=x+-yi#

#"then the magnitude is"#

#•color(white)(x)|z|=|x+-yi|=sqrt(x^2+y^2)#

#5-itox=5" and "y=-1#

#|5-i|=sqrt(5^2+(-1)^2)=sqrt26#

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Answer 2

James Allen

To find the absolute value of |5 - i|, where i is the imaginary unit:

Absolute value of a complex number a + bi is given by √(a^2 + b^2), where a and b are the real and imaginary parts of the complex number, respectively.

Given |5 - i|: a = 5 b = -1 (the imaginary part of -i)

Absolute value = √((5)^2 + (-1)^2) = √(25 + 1) = √26

Therefore, |5 - i| = √26.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.