Question

$(x + 3) \times (x - 3) \\ \\ \\ (2x + 3) \times (2x - 3) \\ \\ \\ ( - 20 + 1) \times (20 - 1) \\ \\ \\ 2)calcule \\ a)(1 - x) \times (x + 1) \\ b)(x + 4) \times (4 - x)$
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Answer 1

Resposta:

Explicação passo-a-passo:

$(x + 3) \times (x - 3)  = x^2 -3x + 3x -9 = x^2-9\\\\(2x  + 3) \times (2x - 3) = 4x^2 - 6x + 6x -9 = 4x^2 - 9\\ \\( - 20 + 1) \times (20 - 1) = ( - 19)  \times (19) = -361\\ \\2)calcule \\ \\a)(1 - x) \times (x + 1)=x+1-x^2-x = 1-x^2\\b)(x + 4) \times (4 - x) = 4x-x^2+16-4x = -x^2+16$