Which of the following can be expressed in the form of a standard quadratic equation?

From the options;

( 2x - 1)³ = x² - 3x + 2 

(2x)³ + (1)³ + 2 (2x)² (-1) + 2 (2x) (-1)²

8x³ + 1 - 8x² + 4x - x² 3x -2 = 0

8x³ + 9x² 7x - 1 = 0 

This  is not quadratic equation  

Option (b):  

=$$\sqrt{ 2x^2 + x + 1}$$

This is quadratic  equation 

(x + 1) (x + 2) = x² - 16

x (x + 2) +1(x + 2) = x² - 16

^\3x + 2 + 18 = 0

3x + 20 = 0 

This is not quadratic equation

(2x + 3)² + 4x - 5 = (2x + 1) (2x - 3)

(2x)² + (3)² + (2) (2x) (3) + 4x -5  = (2x + 1)(2x - 3)

4x² + 9 12x + 4x - 5 = 4x ²​- 6x + 2x - 3 

4 + 16x + 6x - 2x + 3 = 0 

7 + 22x - 2x = 0 

7 + 20x = 0 

This is not quadratic equation

Thus, the correct option is : (b)

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