A) в этом примере √ -корень 4-ой степени
√16a^6/c^3 *√625^11/a^18 = √ (16a^6 *625^11/ с^3*a^18 ) =
= √ (2^4 *(5^11)^4/ с^3*a^12 ) = √ (2^4 *(5^11)^4/ с^3*(a^3)^4 ) =
= 2 *5^11/a^3 √(1/c^3)
б)
6√x^4 * 3√x^5 : √3√x^2 =
3√x^2 * 3√x^5 : 3√x =
3√(x^2 *x^5 : x) =
3√x^(2+5-1) =
3√x^6 =
3√(x^2)^3 =
=x^2