Question

A forma simplificada da expressão {8x² – 6x – 7 – [2x² – 5x – 3 – (2x + 3) – 4x² – 2x – 7] – 7x² – 2x} é: *
x² + x – 7
3x² – 2x – 15
3x² + x + 6
4x² – 2x –​

Answer 1

= {8x² – 6x – 7 – [2x² – 5x – 3 – (2x + 3) – 4x² – 2x – 7] – 7x² – 2x}

= 8x² – 6x – 7 – 2x² + 5x + 3 + 2x + 3 + 4x² + 2x + 7 – 7x² – 2x

= 8x² – 7x² + 4x² – 2x² – 6x + 5x + 2x + 2x – 2x + 7 – 7 + 3 + 3

= 3x² + x + 6