Look at the following function:
Determine for which values of the following is true:
f\left(x\right) < 0
Look at the following function:
Determine for which values of the following is true:
f\left(x\right) < 0
To solve the inequality 2x^2 - 50 < 0 , we follow these steps:
Set the quadratic equation equal to zero to find the roots: .
Rearrange and solve for :
These roots, and , are where the function is equal to zero.
We now examine the intervals determined by these roots to find where the function is negative:
x < -5
-5 < x < 5
x > 5
Since the quadratic is an upward opening parabola (coefficient of is positive), it attains its minimum value between its roots and increases outside them.
Testing a point in each interval:
(For in the interval -5 < x < 5): y = 2(0)^2 - 50 = -50 < 0 .
(Other intervals will be positive) such as or , will have y > 0 .
Thus, the function is negative in the interval -5 < x < 5 .
Therefore, the values of that satisfy 2x^2 - 50 < 0 are:
-5 < x < 5 .
-5 < x < 5