Question

Calcule o valor numérico das expressões:

Answer 1

Olá!!

x+y=

3+6=

9

x-y

3-(+6)

3-6

-3

2x+y=

2.4+(-7)=

8-7=

1

-2x+3y=

-2.-1+3.2=

2+6=

8

x+3y-z=

1+3.2-(+3)=

1+6-3=

7-3=

4

x²+y²

2²+3²=

4+9=

13

3x²-y

3.(-2²)-(-3)

3.+4+3

12+3=

15

a³+2a²+4a

-2³+2.-2²+4.-2

-8+2.-4-8

-8-8-8

-24

Att=Gauzz

Answer 2

Oie, Td Bom?!

a)

$= x + y \\ = 3 + 6 \\ = 9$

b)

$= x - y \\ = 3 - 6 \\ = - 3$

c)

$= 2x + y \\ = 2 \: . \: 4 + ( - 7) \\ = 8 - 7 \\ = 1$

d)

$= - 2x + 3y \\ = - 2 \: . \: ( - 1) + 3 \: . \: 2 \\ = 2 \: . \: 1 + 3 \: . \: 2 \\ = 2 + 6 \\ = 8$

e)

$= x + 3y - z \\ = 1 + 3 \: . \: 2 - 3 \\ = 1 + 6 - 3 \\ = 7 - 3 \\ = 4$

f)

$= x {}^{2} + y {}^{2} \\ = 2 {}^{2} + 3 {}^{2} \\ = 4 + 9 \\ = 13$

g)

$= 3x {}^{2} - y \\ = 3 \: . \: ( - 2) {}^{2} - ( - 3) \\ = 3 \: . \: 2 {}^{2} + 3 \\ = 3 \: . \: 4 + 3 \\ = 12 + 3 \\ = 15$

h)

$= a {}^{3} + 2a {}^{2} + 4a \\ = ( - 2) {}^{3} + 2 \: . \: ( - 2) {}^{2} + 4 \: . \: ( - 2) \\ = ( - 2) {}^{3} + 2 \: . \: ( - 2) {}^{2} - 4 \: . \: 2 \\ = - 8 + 2 \: . \: 4 - 4 \: . \: 2 \\ = - 8 + 8 - 8 \\ = - 8 + 0 \\ = - 8$

Att. Makaveli1996