<span>3x</span>²<span> + 23x − 8 = 3x</span>² + 24x - x - 8 = 3x(x+8) - (x+8) = (x+8)(3x-1)
F(x)/g(x) = (2x +3)(x -1)/(x -1) = 2x +3 . . . . . x ≠ 1
The domain of (f/g)(x) is all real numbers except 1.
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The domain of any rational function necessarilly excludes any values that make the function undefined, that is, that make the denominator zero.
Katie is 6; Cathy is 18!
X- Katie’s age now and 3x -Cathys age now
In 6 years, Katie is 12 and Cathy is 24.
2 x (X+6) = 3x + 6
2x + 12 = 3x + 6
6 = x