To solve the inequality above, first we have to calculate
the roots of the equation 3x^2-13x-10 = 0.
After finding
the roots of the equation, we could write the expression in a factored form
as:
3(x-x1)(x-x2)>0
So,
let's apply the quadratic formula to calculate the
roots:
x1 =
[13+sqrt(169-120)]/6
x1 =
(13+sqrt49)/6
x1 =
(13+7)/6
x1 =
10/3
x2 =
(13-7)/6
x2 =
6/6
x2 =
1
The inequality will be written
as:
3(x -
10/3)(x-1)>0
We'll divide by
3:
(x -
10/3)(x-1)>0
Now, we'll discuss the
inequality:
- the product is positive if the factors are
both positive:
x -
10/3>0
x>10/3
and
x-1>0
x>1
So,
x belongs to the interval (10/3 , +inf.)
- the product is
positive if the factors are both negative:
x -
10/3<0
x<10/3
x-1<0
x<1
So,
x belongs to the interval ( -inf.,1)
Finally, the solution
set of the inequality is the union of the sets identified
above:
( -inf.,1) U (10/3 ,
+inf.)
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