Since 289 is a power of 17, we'll
write:
289 = 17^2
We'll raise
both sides by x;
289^x =
17^2x
We'll re-write the
equation:
17^2x - 12*17^x + 11 =
0
We'll replace 17^x by
t:
t^2 - 12t + 11 = 0
t^2 - t
- 11t + 11 = 0
t(t - 1) - 11(t-1) =
0
(t - 1)(t - 11) = 0
We'll
cancel each factor and w'ell get:
t - 1 = 0 => t1 =
1
t - 11 = 0 => t2 =
11
17^x = t1 <=> 17^x = 1 <=>
17^x = 17^0
Since the bases are matching, we'll apply one
to one property:
x = 0
17^x =
t2<=> 17^x = 11 <=> ln 17^x = ln 11 => x = ln 11/ln
17
The complete set of solutions of the
equation is {0 ; ln 11/ln 17}.
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