Question

1-Sendo A=3x(elevado a 2)-5x-6 , determine o valor A para:
a)x= -2
b)X=2 (elevado a -1)

Answer 1

A = 3x² - 5x - 6

a)  Para x = -2

A = 3.(-2)² - 5.(-2) - 6
A = 3.4 +10 - 6
A = 12 + 4
A = 16

b) Para x = $2^{-1}$

$2^{-1}= \frac{1}{2}$

A = 3.$(\frac{1}{2}) ^{2}$ - 5.$\frac{1}{2}$ - 6

A = 3 . $\frac{1}{4}$ - $\frac{5}{2}$ - 6

A = $\frac{3-10-24}{4}$

A = $\frac{-21}{4}$