Question

dada a função definida por f(x)3x*2-5

a)f(-1)
b)f(-2)
c)f(1/2)
d)f(-3/2)

Answer 1

$a) \: f( - 1) = 3 \times {( - 1)}^{2} - 5 = 3 - 5 = - 2 \\ \\ b) \: f( - 2) = 3 \times {( - 2)}^{2} - 5 = 3 \times 4 - 5 = \\ = 12 - 5 = 7 \\ \\ c) \: f( \frac{1}{2} ) = 3 \times ({ \frac{1}{2} })^{2} - 5 = 3 \times \frac{1}{4} - 5 = \\ = \frac{3}{4} - \frac{20}{4} = \frac{ - 17}{4} \\ \\ d) \: f( \frac{ - 3}{2} ) = 3 \times { (\frac{ - 3}{2} })^{2} - 5 = \\ = 3 \times \frac{9}{4 } - 5 = \frac{27}{4} - \frac{20}{4} = \frac{7}{4}$