Данила9 лет назад
1. а ) 6 ^ 15 * 6 ^ ( - 13 ) = 6 ^ ( 15 + ( - 13 ) ) = 6 ^ ( 15 - 13 ) = 6 ^ 2 = 6 * 6 = 36 ;
б ) 4 ^ ( - 6 ) : 4 ^ ( - 3 ) = 4 ^ ( - 6 - ( - 3 ) ) = 4 ^ 9 = 256 * 256 * 4 = 262 144 ;
в ) ( 5 ^ ( - 1 ) ) ^ 3 = 5 ^ ( - 1 * 3 ) = 5 ^ ( - 3 ) = 1 / 5 ^ 3 = 1 / 125 ;
2. а ) ( x ^ ( - 2 ) ) ^ ( - 4 ) * x ^ ( - 7 ) = x ^ ( 2 * 4 ) * x ^ ( - 7 ) = x ^ 8 * x ^ ( - 7 ) = x ^ ( 8 - 7 ) = x;
б) 1.2 a^( -5 ) * b ^ 8 * 5 * a^6b^( -6 ) = 1.2 * 5 * a ^ ( - 5 + 6 ) * b ^ ( 8 - 6 ) = 6 * a * b ^ 2 ;
3. а) (2/3a^-4b^-2)^-2 = 2 ^ ( - 2 ) * 1 / (3 ^ ( - 2 ) * a ^ ( - 4 * ( - 2 ) ) * b ^ ( - 2 * ( - 2 ) ) = 1 / 4 * 1 / ( 9 * a ^ 8 * b ^ 4 ) = 1 / 36 * 1 / ( a ^ 8 * b ^ 4 ) ;
б) (5a^-2/6b^-1)^-2 * 10a^3b^4 = 5 ^ ( - 2 ) * a ^ 4 / ( 6 ^ ( - 2 ) * b ^ 2 ) * 10a^3b^4 = 1 / 25 * 36 * 10 * a^7b^2 = 1 / 5 * 36 * 2 * a^7b^2 = 14* a ^ 7 * b ^ 2;
4. 5^-9 * 25^-2/ 125^-4 = 5^-9 * ( 5 ^ 2 ) ^-2/ ( 5 ^ 3 )^-4 = 5 ^ ( - 9 - 4 - ( - 12 ) ) = 5 ^ ( - 1 ) = 1 / 5 = 0.2 ;
5. (6.8 * 10^6) * (4.5 * 10^-8) = 6.8 * 4.5 * 10 ^ ( - 2 ) = 0.306;
6. (а^-1 + b)(a + b^-1)^-1 = ( a ^ ( - 1 ) + b ) / ( a + b ^ ( - 1 ) ) = ( 1 / a + b ) / ( a + 1 / b ) = ( 1 + a * b ) / a / ( ( a * b + 1 ) / b ) = ( 1 + a * b ) / a * b / ( a * b + 1 ) = b / a .