(а+b)•30a^2b 2a 2•2
1) ----------------------- = ------ = ------- = 1–1
15ab•(a–b)(a+b) a–b 2+2
= 0
4b(a–b)•(а^3+1) 4b
2) ---------------------- +20 = ---- +20 =
а(а^3+1)•5(а–b) 5a
= –16/25+20 = (-16+500)/25=19,36
(1–9b)(1+9b)•(a+5) 1
3) ------------------------- – ------ =
(a–5)(a+5)•(9b+1) a–5
1–9b 1 1–9b–1 9b
= -------- – ------- = ----------- = – ------ =
a–5 a–5 a–5 a–5
= –9•(–2,5)/(–5) = –4,5
6a^2(b–1)•5(b+2) 5
4) ------------------------ + ---- =
(b+2)•12a^3 2a
5(b–1) 5 5b–5+5 5b 5•11
= --------- + ---- = ------------ = ----- = ------
2a 2a 2a 2a 2•10
= 55/20 = 2,75