3.22.
а) 100d²/(100d² -9) -160d/(3-10d)(10d +3) +(9 -100d)/(100d² -9)=
100d²/(100d² -9) +160d/(10d-3)(10d +3) +(9 -100d)/(100d² -9)=
100d²/(100d² -9) +160d/(100d²-9)+(9 -100d)/(100d² -9)=
(100d² +160d +9 -100d)/(100d²-9) =(100d²+60d+9) /(100d²-9) =(10d+3)²/(10d -3)(10d+3)=
(10d+3)/(10d -3).
б) 49/(49a² -16)+(56a+33)/(7a-4)(-7a -4) -49a²/(16-49a²)
=49/(49a² -16) - (56a+33)/(7a-4)(7a+4) +49a²/(49a² -16 ) =
(49 -56a-33 +49a²)/(49a² -16 ) =(49a² -56a +16)/(49a²-16) =(7a -4)²/(7a-4)(7a+4)=
(7a -4)/(7a+4).