Question

lg^2(x-1)^2 +lg(x-1)^3 =25

Answer 1

lg^2(x-1)^2 +lg(x-1)^3 =25

одз x > 1

4*lg^2(x-1) + 3lg(x-1)  - 25 = 0

lg(x - 1) = t

4t^2 + 3t - 25 = 0

D = 9 + 400 = 409

t12 = (-3 +- √409)/8

lg(x - 1) = (-3 +- √409)/8

x12 = 10^(-3 +- √409)/8  + 1