Question

Questões
1 - Efetue as seguintes subtrações:
a) (5x2 - 4x + 7) - (3x2 + 7x - 1)
b) (6x2 - 6x + 9) - (3x2 + 8x - 2)
c) (7x - 4y + 2) - (2x - 2y + 5)
d) (4x - y - 1) - (9x + y + 3)
e) (-2a2 - 3a + 6) -(-4a? - 5a +6)
f) (4x3 - 6x2 + 3x) - (7x3 - 6x² + 8x)​

Answer 1

Resposta:

A)12-11x

B)17-14x

C) 5x-2y-3

D) -5x-2y-4

E) 2a

F)

$6 {x}^{2} - 5x - 21$

Explicação passo-a-passo:

Contas:

A) (5x2 - 4x + 7) - (3x2 + 7x - 1)

(10-4x+7) - (6+7x-1)

(17-4x) - (5+7x)

(17-4x) - (5+7x)

17-4x-5-7x

12-11x

B) (6x2 - 6x + 9) - (3x2 + 8x - 2)

(12-6x+9) - (6+8x-2)

(21-6x) - (4+8x)

21-6x-4-8x

17-14x

C) (7x - 4y + 2) - (2x - 2y + 5)

7x-4y+2-2x+2y-5

5x-2y-3

D) (4x - y - 1) - (9x + y + 3)

4x-y-1-9x-y-3

-5x-2y-4

E) (-2a2 - 3a + 6) -(-4a - 5a +6)

(-4a-3a+6)-(-9a+6)

(-7a+6) + 9a-6

-7a+6+9a-6

2a

F) (4x3 - 6x2 + 3x) - (7x3 - 6x² + 8x)

$(12 - 12 + 3x) - (21 - 6 {x}^{2} + 8x)$

$(3x) - 21 + 6 {x}^{2} - 8x$

$3x - 21 + 6 {x}^{2} - 8x$

$- 5x - 21 + 6 {x}^{2}$

$6 {x}^{2} - 5x - 21$