Question

Помогите пожалуйста, ничего не понял

Answer 1

1.

Решаем по формуле

$(a - b) {}^{2} = {a}^{2} - 2ab + {b}^{2}$

а)

${4x}^{2} - 4x + 1$

Б)

$(3a + c) {}^{2} = {9a}^{2} + 6ac + {c}^{2}$

В)

Этот пример Решаем по формуле

${a}^{2} - {b}^{2} = (a - b)(a + b)$

${y}^{2} - 25$

Г)

${16b}^{2} - 25 {c}^{2}$

2.

${x}^{2} - {y}^{2} - {x}^{2} - 3 {y}^{2} = - 4 {y}^{2}$

3.

а)

$(4y - 0.5)(4y + 0.5)$

Б)

$(a + 5b) {}^{2}$

4.

$25 - 10x + {x}^{2} - 2.5x - {x}^{2} =0 \\ - 12.5x + 25 = 0 \\ - 12.5x = 0 - 25 = - 25 \\ x =- 25 \div ( - 12.5)$

$x = 2$

5.

$a) {4a}^{2} - {b}^{4}$

Б)

${x}^{2} - 12 {x}^{4} + 36 {x}^{6}$

В)

$( {y}^{2} + 2yb + {b}^{2} )( {y}^{2} - 2yb + {b}^{2} ) = \\ {y}^{4} - 2 {y}^{3} b + {y}^{2} {b}^{2} + 2 {y}^{3} b - 4 {y}^{2} {b}^{2} \\ + 2y {b}^{3} + {y}^{2} {b}^{2} - 2y {b}^{3} + {b}^{4} =$

${y}^{4} - 2 {y}^{2} {b}^{2} + {b}^{4}$

6.

а)

$( \frac{1}{9} a - 0.3 {c}^{2} )( \frac{1}{9} a + 0.3 {c}^{2} )$

Б)

${b}^{2} + 16b + 64 - 4 {b}^{2} = \\ - 3 {b}^{2} + 16b + 64$

В)

$({a}^{3} ) {}^{3} - {b}^{3} = ( {a}^{3} - b)(( {a}^{3} ) {}^{2} + {a}^{3} b \\ + {b}^{2} ) = ( {a}^{3} - b)( {a}^{6} + {a}^{3} b + {b}^{2} )$