Question

(Mack-sp) O valor de 2x^0+x^3/4+18x^-1/2, quando x=81

Answer 1

.
$2x^0+x^{ \frac{3}{4}}+18x^{- \frac{1}{2} } \\ \\ para~~x=81 \\ \\ 2(81)^0+81^{ \frac{3}4} +18(81)^{- \frac{1}{2} }= \\ \\ 2(1)+ \sqrt[4]{81^3} +18. \sqrt{81^{-1} }= \\ \\ 2+ \sqrt[4]{(3^4)^3} +18 \sqrt{ \frac{1}{3^4} } = \\ \\ 2+ \sqrt[4]{3^{12} }+18. \frac{1}{3^2} = \\ \\ 2+3^3+18. \frac{1}{9} = \\ \\ 2+27+2=\fbox{ 31 }$