Given the inequality:
$$\sqrt{2 x} - 3 > 4$$
To solve this inequality, we must first solve the corresponding equation:
$$\sqrt{2 x} - 3 = 4$$
Solve:
Given the equation
$$\sqrt{2 x} - 3 = 4$$
Because equation degree is equal to = 1/2 - does not contain even numbers in the numerator, then
the equation has single real root.
We raise the equation sides to 2-th degree:
We get:
$$\left(\sqrt{2 x}\right)^{2} = 7^{2}$$
or
$$2 x = 49$$
Divide both parts of the equation by 2
x = 49 / (2)
We get the answer: x = 49/2
$$x_{1} = \frac{49}{2}$$
$$x_{1} = \frac{49}{2}$$
This roots
$$x_{1} = \frac{49}{2}$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} < x_{1}$$
For example, let's take the point
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{1}{10} + \frac{49}{2}$$
=
$$\frac{122}{5}$$
substitute to the expression
$$\sqrt{2 x} - 3 > 4$$
$$-3 + \sqrt{\frac{2 \cdot 122}{5}} > 4$$
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2*\/ 305
-3 + --------- > 4
5
Then
$$x < \frac{49}{2}$$
no execute
the solution of our inequality is:
$$x > \frac{49}{2}$$
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