1. 3)2. 1) a–4=0 (не равно) а не равно 42) 25х^2–49=0 (не равно)(5х–7)(5х+7)=05х=7; 5х=-7х=7/5; х=-7/5х не равно 7/5 и -7/53. 1) 25х^5у^2 5х^2 -------------- = ------- 35х^3у^3 7у2) 3а 3a 3 --------- = --------- = ------ da+5a a(d+5) d+53) ab+3b b(a+3) a+3 --------- = --------- = ------- b^2 b^2 b4) a^2–4 (a–2)(a+2) ---------- = --------------- = a–2 a+2 a+25) m^2–n^2 (m–n)(m+n) m–n -------------- = ---------------- = -------- 3m+3n 3(m+n) 36) a^2–m^2–2mn–n^2 ------------------------------ = 8a–8m–8n a^2–(m+n)^2 (a–m–n)(a+m+n)= ------------------- = ----------------------- = 8(a–m–n) 8(a–m–n) a+m+n= ----------- 84. 1) 8a^2b 3bc^2 24a^2b^2c^2 --------- • --------- = -------------------- = 9c 4a^3b 36a^3bc 2bc= ------- 3a2) 12x^2y 168x^2z^2 24x^2 : ----------- = ---------------- = 7z^2 12x^2y 14z^2= -------- y3) a+2 b^2 (a+2)b^2 b ------ • ---------- = --------------- = ------- b a^2–4 b(a–2)(a+2) a–b4) ab+b^2 b^2 b(a+b)•14a 2(a+b) ---------- : ------ = --------------- = -------- 7a 14a 7ab^2 b5) m+n m–n m+n ------- • ------- = ------- m–n m m6) x x^2 3x(x–3) 3 ------ : -------- = ------------ = --- x–3 3x–9 (x–3)x^2 x