Question

1) (5 + x)2
2) (с- 6)2
3) (7 + y)(7 - у)
4) (3а - 4)
5) (8 - 9b)(8 +9b)
6) (a' -10a)
7) (5x2 + x)5x2 - x)

Answer 1

1) (5 + x)² = 5² + 2 * 5 * x + x² = 25 + 10x + x².

2) (c – 6)² = c² – 2 * c * 6 + 6² = c² – 12c + 36.

3) (7 + y)(7 – y) = 7² - y².

4) (3a – 4)² = (3a)² – 2 * 3a * 4 + 4² = 9a² - 24a + 16.

5) (8 – 9b)(8 + 9ab) = 8² – (9b)² = 64 – 81b.

6) (a⁵ – 10a)² = (a⁵)² – 2 * a⁵ * 10a + (10a)² = a¹⁰ – 20a⁶ + 100a².

7) (5x² + x)(5x² – x) = (5x²)² – x² = 25x⁴ – x².