Question 67827
12. (3/x^2-5x+6)-(5/(x-2)^2)
The least common denominator is (x-2)^2(x-3)
Rewrite each fraction with the lcd as its denominator as follows:

= 3(x-2)/lcd  - 5(x-3)/lcd
Combine the numerators to get:

=[3x-6-5x+15]/lcd

=(-2x+9)/[(x-2)^2(x-3)]

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28.{(1/x+h)-(1/x)/h}

lcd is  h(x+h)

Rewrite the fractions to get:

= h/lcd - (1/x)(x+h))/lcd

Combine the numerators to get:

=[h -(1 + h/x)]/lcd

=[ (xh -x- h)/x]/lcd

=(xh-x-h)/[hx(x+h)]

Cheers,
Stan H.