Question

Dada a função f(x)=5x+3/x-1, calcule f(2/3)

Answer 1

$f_{(x)}=5x+\dfrac{3}{x}-1\\\\\\ f_{(\frac{2}{3})}=5\left(\dfrac{2}{3}\right)+\dfrac{\dfrac{3}{1}}{\dfrac{2}{3}}-1\\\\\\ f_{(\frac{2}{3})}=\dfrac{10}{3}+\dfrac{9}{2}-1\\\\\\ f_{(\frac{2}{3})}=\dfrac{20+27-6}{6}\\\\ \boxed{f_{(\frac{2}{3})}=\dfrac{41}{6}}$

Bons estudos!

Answer 2

• Substitua x por 2/3 e resolva.

f(x) = 5x + 3/x - 1

f(2/3) = 5 . 2/3 + 3/(2/3) - 1

f(2/3) = 10/3 + 3 . 3/2 - 1

f(2/3) = 10/3 + 9/2 - 1

f(2/3) = (20 + 27 - 6)/6

f(2/3) = (47 - 6)/6

f(2/3) = 41/6

Resposta: 41/6