We'll multiply all terms both sides by the least common
denominator.
2*log3 (x)*log3 (x) + 2 = 5*log3
(x)
2*[log3 (x)]^2 - 5*log3 (x) + 2 =
0
We'll replace log3 (x) by
t.
2t^2 - 5t + 2 = 0
We'll
apply quadratic formula:
t1 = [5+sqrt(25 -
16)]/4
t1 = (5+3)/4
t1 =
2
t2 = 1/2
But log3
(x)=t.
log3 (x)=t1 <=> log3
(x)=2
We'll take antilogarithms and we'll
get:
x = 3^2
x =
9
log3 (x)=t2
x = sqrt
3
Since both values are positive, we'll
accept them as solutions of equation: {sqrt3 ;
9}.
No comments:
Post a Comment