Question

(x^2-81)/(x^2-4)

Which is the values of x?

Answer 1

x can be any number excluding 2 and -2

Explanation:

x² - 81 / x² - 4

= x² - 9² / x² - 2²

as we know the formula, a² - b² = (a + b)(a - b)

thus,

x² - 9² / x² - 2²

= (x + 9)(x - 9) / (x + 2)(x - 2)

we can't have a 0 in the denominator, x can be any value apart from -2 and 2 as both these values will give 0 in the denominator which is considered a significant error