Question

efetue as multiplicações

A) (3x + 1) (3x - 1)
B) (5x + 9) (5x - 9)

Answer 1

A) (3x+1) (3x-1)
9x²-3x +3x -1
9x² -1

B) (5x + 9) (5x - 9)
25x² -40x +40x -91
25² - 91

Answer 2

A) (3x + 1) (3x - 1)

9x² - 3x + 3x - 1

9x² - 1

B) (5x + 9) (5x - 9)

25x² - 45x + 45x - 81

25x² - 81