1)14 xy^2 / 35 x^3 z= 2 y^2 / 5 x^2 z;
2) 9(x+z)^4 / 3(x+z)^6= 3/ (x+z)^2;
3) 2 (a- b) ^5 / 18(b - a)^2= (a- b)^5 / 9(a - b)^2= (a - b)^3 / 9.
1. 8^13 / 8^11 = 8^(13 - 11) = 8^2 = 64;
2. 81 / 3^6 = 81 / 3^2*3^4 = 81/ 9*81 = 1/9;
3. 6^4 / 2^3 = (3*2)^4 / 2^3 = 3^4 * 2^4 / 2^3 = 3^4 * 2^(4 - 3) = 81 *2^1 = 81 *2 = 162.
1) 83²+33²+83*66 = 83²+2*83*33+33² = (83+33)² = 116²=13456
2) 19,3²+2*19,3*30,7+30,7² = (19,3+30,7)² = 50² = 2500
3) 31,8²-2*31,8*21,8+21,8² = (31,8-21,8)² = 10² = 100
4) 99*101² =(100-1)(100+1) = (100-1)(100²+200+1) = 99*10201=1009899
5) 201*199= (200+1)(200-1) = 200²-200+200-1 = 40000-1 = 39999
4 и 5 номера может у тебя неправильно переписаны?
2) 15b-20c / 10b = 5(3b-4c) / 10b = 3b-4c / 2b
4) a-3b / a^2+3ab = a-3b / a(a+3b)
6) 3x^2+15xy / x+5y = 3x(x+5y) / x+5y = 3x
8) 5x-15y / x^2-9y^2 = 5(x-3y) / (x-3y)(x+3y) = 5 / x+3y
10) 6cb-18c^2 / (b-3c)^3 = 6c(b-3c) / (b-3c)^3 = 6c / (b-3c)^2
12) a^3-b^3 / a-b = (a-b)(a^2+ab+b^2) / a-b = a^2+ab+b^2