Question

2) Efetue as operações:
A) (7x +5x2 - 2x + 8) + (2x2 + 3x - 3)

B) (9x - 7x + 1) - (4x + 7) C) (4x - 3x3 + 1) + (3x3 + 3x? – 7x +2)

D) (2x2 + 2x - 1) - (2x2 - 2x - 1)

Answer 1

Explicação passo-a-passo:

A) (7x +5x2 - 2x + 8) + (2x2 + 3x - 3)

5x²+5x+8+2x²+3x-3=0

7x²+8x+5=0

$delta = b ^{2} - 4ac \\ delta = 8 ^{2} - 4 \times 7 \times 5 \\ delta = 64 - 140 \\ delta = - 76$

B )(9x - 7x + 1) - (4x + 7)

2x+1-4x-7=0

-2x-6=0

-2x=6×(-1)

2x=-6

x=-6÷2

x=-3

C) (4x - 3x3 + 1) + (3x3 + 3x? – 7x +2)

-3x³ +4x +1 +3x³ +3x² -7x +2=0

3x² -3x +3³0

$delta = b ^{2} - 4ac \\ delta = ( - 3) ^{2} - 4 \times 3 \times 3 \\ delta = \: 9 \: - \: 36 \\ delta = - 27$

D) (2x² + 2x - 1) - (2x² - 2x - 1)

2x² +2x -1 -2x² +2x +1=0

4x=0

x=0