Question

Simplifique as expressões:
A) (2x + 1)^2 + (x - 5)^2

B) (x - 3)^2 - (x + 2)^2 + (x + 3)(x - 1)

Answer 1

A) (2x + 1)^2 + (x - 5)^2

= (2x + 1)² + (x - 5)²

= 4x² + 2.2x.1 + 1 + x² - 2.5x + 25

= 4x² + 4x + 1 + x² - 10x + 25

= 4x² + x² + 4x - 10x + 1 + 25

= 5x² - 6x + 26

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B)
= (x - 3)^2 - (x + 2)^2 + (x + 3)(x - 1)

= (x - 3)² - (x + 2)² + (x² - x + 3x - 3)

= x² - 2.3x + 9 - [x² + 2.2x + 4] + x² + 2x - 3

= x² - 6x + 9 - [x² + 4x + 4] + x² + 2x - 3

= x² - 6x + 9 - x² - 4x - 4 + x² + 2x - 3

= - 6x + 9 - 4x - 4 + x² + 2x - 3

= x² - 6x - 4x + 2x + 9 - 4 - 3

= x² - 10x + 2x + 9 - 7

= x² - 8x + 2