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How do you multiply #(k + 3)(k – 3)#?

Answer 1

Nathan Axel

#k^2-9# This is a difference of squares where: #(x^2-y^2) = (x+y)(x-y)#

If we let #x=k# and #y=3# #((k)^2-(3)^2) = (k+3)(k-3)#

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Answer 2

Abigail Allen

To multiply ((k + 3)(k - 3)), you can use the distributive property or the FOIL method. Using the distributive property, you would multiply each term in the first expression by each term in the second expression and then combine like terms. Using the FOIL method, which stands for First, Outer, Inner, Last, you would multiply the first terms, then the outer terms, then the inner terms, and finally the last terms, and then combine like terms. Both methods will give you the same result.

Here's the step-by-step process:

Using the distributive property:

(k \times k = k^2)
(k \times (-3) = -3k)
(3 \times k = 3k)
(3 \times (-3) = -9)

Combine like terms: ((k^2 - 3k + 3k - 9))

Simplify: (k^2 - 9)

Using the FOIL method:

First: (k \times k = k^2)
Outer: (k \times (-3) = -3k)
Inner: (3 \times k = 3k)
Last: (3 \times (-3) = -9)

Combine like terms: ((k^2 - 3k + 3k - 9))

Simplify: (k^2 - 9)

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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.