Question

Dado o gráfico da função exponencial f(x)=9*x. A soma dos valores de f(1/2),f(2),f(3) e f(4) é igual a:

a)7374
b)729
c)7371
d)81
e)Mais de 10000

Answer 1

$\displaystyle f(x)=9^x\\\\\\ f(\frac{1}{2})=9^{\frac{1}{2}}\\\\ f(\frac{1}{2})=\sqrt{9}\\\\ f(\frac{1}{2})=3\\\\\\ f(2)=9^2\\\\ f(2)=9.9\\\\ f(2)=81\\\\\\ f(3)=9^3\\\\ f(3)=9.9.9\\\\ f(3)=81.9\\\\ f(3)=729\\\\\\ f(4)=9^4\\\\ f(4)=9.9.9.9\\\\ f(4)=81.81\\\\ f(4)=6561\\\\\\ f(\frac{1}{2})+f(2)+f(3)+f(4)\\\\ 3+81+729+6561\\\\ 84+7290\\\\ \fbox{7374}\\\\ \text{Portanto, letra A.}$