Question

Срочно даю 30 бал. До четверга надо пж.

Answer 1

Ответ:

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Answer 2

Ответ:

В решении.

Объяснение:

1.

1) 7⁻⁵ * 49² =

=7⁻⁵ * (7²)² =

=7⁻⁵ * 7⁴ =

=1/7⁵ * 7⁴ =

= 7⁴/7⁵ = 1/7.

2) (1/2)¹⁸ : (1/2)²¹ =

= (1/2)¹⁸⁻²¹ =

= (1/2)⁻³ =

= 1 : (1/2)³ =

=1 : 1/8 = 8.

3) ((-0,3)²)⁻¹ = (0,09)⁻¹ = 1 : 0,09  = 1 : 9/100 = 100/9 = 11 и 1/9.

2.

1) 36х⁴b³ * (6xb⁻³)⁻² =

= 36х⁴b³ * 6⁻²x⁻²b⁶ =

= 36х⁴b³ * 1/6²* 1/x² *b⁶ =

= (36x⁴b³*b⁶)/36x² =

= 36х⁴b⁹/36x² =

= x²b⁹.

2) (6а/7b⁻¹)⁻² * (49a⁻²/18b⁻³)⁻¹ =

= (6⁻²a⁻²/7⁻²b²) * (49⁻¹a²/18⁻¹*b³)=

= (1/6²*1/a²) : (1/7²*b²) * (1/49*a²) : (1/18 *b³) =

= (1/36a²) : (b²/49) * (a²/49) : (b³/18) =

= (1 * 49)/(36a² * b²) * (a² * 18)/(49 * b³) =

= (49/36a²b²) * (18a²/49b³) =

= (49 * 18a²) /(36a²b² * 49b³) =

= 1/2b⁵ = 0,5b⁵.

3. (a - b)⁻² * (a⁻² - b⁻²) =  -(a+b)/a²b²(a-b).

1) a⁻² - b⁻² = 1/a² - 1/b² = (b² - a²)/a²b² = (b-a)(b+a)/a²b²;

2) (a - b)⁻² = 1/(a-b)²;

3)1/(a-b)² * (b-a)(b+a)/a²b² = -(a-b)(a+b)/a²b²(a-b)² = -(a+b)/a²b²(a-b).