Question 352439

f (x) = {{{log(3,(8x + x^-8))}}}

f(x) = (1/ln(3))*ln(8x + x^-8)

f'(x) = (1/ln(3))*(1/(8x + x^-8))*(8 - 8x^-9)

@ x = 1: f'(x) = (1/ln(3))*(1/(8 + 1))*(8 - 8)
= 0

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f(1) = log(3,9) = 2

--> y = 2 is the line tangent at x = 1