1. (5a - 12b) (5a + 12b) =

2. (6a + 5b) ²=

3. (8a - b) ²=

4. (а + 3) (а² - 3 а + 9) =

5. (b - 2) (b² + 2b + 4) =

6. ( - a² + 9) (a² + 9) =

7. (a⁸ + b ⁸) (a⁴ + b ⁴) (a⁴ - b ⁴) =

1) (5a-12b) (5a+12b) = (5a-12b) * 5a + (5a-12b) * 12b = 25a²-60ab+60ab-144b²=25a-144b² 2) (6 а+5b) ² = 6²a²+5²b² 3) (8a-b) ²=8²a²-b² 4) (а + 3) (а² - 3 а + 9) = (а+3) * a² + (a+3) * (-3a) + (a+3) * 9=a³+3a²-3a²-9a+9a+27=a³+27 5) (b - 2) (b² + 2b + 4) = (b-2) * b² + (b-2) * 2b + (b-2) * 4=b³-2b²+2b³+4b+4b-8=3b³-2b²+8b 6. ( - a² + 9) (a² + 9) = (-a²+9) * a² + (-a²+9) * 9=-a⁴+9a²-9a+81=-a⁴+81