General simplification
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$$- 2 x^{2} + 5 x - 2$$
The perfect square
Let's highlight the perfect square of the square three-member
$$\left(\left(-2\right) x^{2} + 5 x\right) - 2$$
To do this, let's use the formula
$$a x^{2} + b x + c = a \left(m + x\right)^{2} + n$$
where
$$m = \frac{b}{2 a}$$
$$n = \frac{4 a c - b^{2}}{4 a}$$
In this case
$$a = -2$$
$$b = 5$$
$$c = -2$$
Then
$$m = - \frac{5}{4}$$
$$n = \frac{9}{8}$$
So,
$$\frac{9}{8} - 2 \left(x - \frac{5}{4}\right)^{2}$$
$$\left(x - 2\right) \left(x - \frac{1}{2}\right)$$
Assemble expression
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$$- 2 x^{2} + 5 x - 2$$
Combining rational expressions
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$$x \left(5 - 2 x\right) - 2$$
$$- \left(x - 2\right) \left(2 x - 1\right)$$
Rational denominator
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$$- 2 x^{2} + 5 x - 2$$