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How do you find the additive and multiplicative inverse of -8?

Answer 1

Abigail Allen

Additive inverse, #+8#
Multiplicative inverse, #-1/8#

For a number #a#, it's multiplicative inverse #b# is such that #a*b = 1# which is the multiplicative identity.

For a number #a#, it's additive inverse #c# would be such that # a + c = 0# where #0# is additive identity.

Thus, for #a = -8# It's additive inverse be #c#.

Then #-8 + c = 0#

Now, adding #8# to both sides,

#c = 8#.

Let the multiplicative inverse be #b#.

Then #a*b = 1# #implies -8*b = 1#

Multiplying both sides with #-1/8#

#b = -1/8#

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Answer 2

Jace Anderson

Additive Inverse: 8 Multiplicative Inverse: -1/8

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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.