f(x)+4f(1/x)=15x
<span>X+Pi/6= pi+2pi nx=5pi/6 + 2 pi n </span>
(1,5a⁻²b)(4a³b⁻⁴) = 6a⁻²⁺³b¹⁻⁴ = 6ab⁻³ = 6a/b³;