FUNCTIONS 3

If F(x) = log₃x, Find F(¹/₁₃₁₂₂)

Solution

F(x) = log₂x

F(¹/₁₃₁₂₂) = log₃(¹/₁₃₁₂₂)

F(¹/₁₃₁₂₂) = log₃13122^-1

F(¹/₁₃₁₂₂) = log₃(3⁹)^-1             [since 13122 = 3⁹ by prime factorization]

F(¹/₁₃₁₂₂) = log₃3^{(9 x -1)}

F(¹/₁₃₁₂₂) = log₃3^-9

F(¹/₁₃₁₂₂) = -9log₃3

F(¹/₁₃₁₂₂) = -9 x 1

F(¹/₁₃₁₂₂) = -9

  

Therefore F(¹/₂₁₈₇) = -9

TRY THIS...............

If F(x) = log₃x, Find F(¹/₇₂₉)