(4a^2-4a+1)/(2a-1) = ((2a-1)(2a-1))/(2a-1) = 2a-1
(4a+3)/(16a^2-9) = (4a+3)/(4a+3)(4a-3) = 1/(4a-3)
(3-b)/(9-6b+d^2) = -(b-3)/(6b-d^2-9)
(4a^2-4a+1)/(2a-1) = ((2a-1)(2a-1))/(2a-1) = 2a-1
(4a+3)/(16a^2-9) = (4a+3)/(4a+3)(4a-3) = 1/(4a-3)
(3-b)/(9-6b+d^2) = -(b-3)/(6b-d^2-9)