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How do you factor: #y=x^2 - 5#?

Answer 1

Apply the difference of squares formula to find that
#x^2 - 5 = (x + sqrt(5))(x - sqrt(5))#

The difference of squares formula states that #a^2 - b^2 = (a+b)(a-b)# (This is easy to verify by expanding the right hand side)

While #5# may not be a perfect square, it is still the square of something... specifically, it is the square of #sqrt(5)# Then, applying the formula, we have

#x^2 - 5 = x^2 - (sqrt(5))^2 = (x + sqrt(5))(x - sqrt(5))#

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Answer 2

Kennedy Adams

To factor the expression y = x^2 - 5, you can use the difference of squares formula.

y = (x + √5)(x - √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.