Simplify and find all numbers that must be excluded from the domain of the simplified rational expression.
please show work...
when the denominator equals to zero, the function is not defined. So, find the values at which the denominator of the function is zero and exclude them from the domain.
how do i do that?
a^2+4a/a^2-16 If a^2 + (4a/a^2) - 16, then a ≠ 0, since 4/0 is undefined; 0 must be excluded from the domain of the given rational expression. If a^2 + 4a/(a^2 - 16) = a^2 + 4a/(a+ 4)(a - 4), then x ≠ -4 and x ≠ 4; -4 and 4 must be excluded from the domain of the given rational expression. If (a^2+4a)/(a^2-16) = a(a + 4)/(a+ 4)(a - 4) = a/(a-4), then x ≠ 4; 4 must be excluded from the domain of the given rational expression.
the next one= 8-x/x^2-7x-8 If 8 - (x/x^2) - 7x - 8; then x ≠ 0, since 1/0 is undefined; 0 must be excluded from the domain of the given rational expression. If 8 - x/(x^2 - 7x - 8) = 8 - x/(x - 8)(x + 1); then x ≠ 8 and x ≠ -1; 8 and -1 must be excluded from the domain of the given rational expression. If (8 - x)/(x^2 - 7x - 8) = -(x - 8)/(x - 8)(x + 1) = -1/(x + 1); then x ≠ -1; -1 must be excluded from the domain of the given rational expression. If 8-(x/x^2-7x) - 8 = 8 - (x/x(x - 7) - 8; then x ≠ 7; 7 must be excluded from the domain of the given rational expression.
hope i helped;)
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