Question 535345
Find the domain of the logarithmic function.. 
f(x)= log(x^2-17x+72)
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x^2-17x+72 must be > 0
(x-9)(x-8) > 0
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Draw a number line and plot x=8 and x=9
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Look for solutions in the intervals:
Try x = 0: -*- > 0 ; true, so solutions in (-oo,8)
Try x = 8.5: -*+ > 0 ; false
Try x = 9.5: +*+ > 0 ; true, so solutions in (9,+oo)
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Domain: (-oo,8)U(9,+oo)
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Cheers,
Stan H.
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