№1
4b a 2 4b a 2 4b*b - a*a + 2(a-2b)
1) --------- + --------- + -- = --------- - ---------- + -- = -------------------------- =
a(a-2b) b(2b-a) b a(a-2b) b(a-2b) b ab(a-2b)
4b²-a²+2a-4b (a-2b)(a+2b)+2(a-2b) (a-2b)(a+2b+2) a+2b+2
= ------------------ = - ---------------------------- = - -------------------- = - ----------
ab(a-2b) ab(a-2b) ab(a-2b) ab
1 9x x²+3x+9-9x (x-3)² x-3
2) ---- - ------------------- = ------------------- = ------------------- = ----------
x-3 (x-3)(x²+3x+9) (x-3)(x²+3x+9) (x-3)(x²+3x+9) x²+3x+9
№2
b²-3b+9 3(b+3)
------------- * --------------------(сокращаются b+3 и b+3; b²-3b+9 и b²-3b+9)
(b-3)(b+3) (b+3)(b²-3b+9)
3
= -------------
(b-3)(b+3)
b 3 b-3 1
----- - ----- = -------------- = -----
b²-9 b²-9 (b-3)(b+3) b+3
№5
2x 40x 5 4x²-10x+40x+10x+25 (2x+5)²
1)--- + ------ - -- = ---------------------------- = ----------
1 2x-5 1 2x-5 2x-5
4x²-20x+25-4x²+22x-20 2x+5
2) ------------------------------- = ---------
4x²-20x+25 (2x-5)²
(2x+5)² (2x-5)²
3)--------- * --------- = (2x+5)(2x-5)
2x-5 2x+5
4) 4x²-25+16= 4x²-9