Question

Dada a função f:R-R,definida por f(x) = -9x+3,calcule

a) f(3)
b) f(-2)
c) f(0)
d) x sendo f(x)=12

Answer 1

a)
$3 = - 9x + 3$
$9x = 3 - 3$
$9x = 0$
b)
$- 2 = - 9x + 3$
$9x = 3 + 2$
$9x = 5 \\ x = \frac{5}{9} = aproximadamente \\ 0.5$

c )
$9x = 3$
$x = \frac{3}{9}$
$x = aproximadamente \: 0.3$
d)
$x = - 9x + 3$
$x + 9x = 3$
$10x = 3$
$x = \frac{3}{10}$
$x = 0.3$