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How do you find the absolute value of #-2-i#?

Answer 1

Anna Allen

#|-2-i|=sqrt5#

Absolute value of a complex number #a+ib# is written as #|a+ib|# and its value as #sqrt(a^2+b^2)#.

Hence, absolute value of #-2-i# is #sqrt((-2)^2+(-1)^2)=sqrt(4+1)=sqrt5#.

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Answer 2

Elias Ackerman

To find the absolute value of ( -2 - i ), you use the absolute value formula for complex numbers:

[ |a + bi| = \sqrt{a^2 + b^2} ]

For ( -2 - i ), where ( a = -2 ) and ( b = -1 ), the absolute value is:

[ | -2 - i | = \sqrt{(-2)^2 + (-1)^2} = \sqrt{4 + 1} = \sqrt{5} ]

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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.