Question

(2x +3y+2)² -(2x -3y + z)² = ?

Answer 1

Solution :

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We know the algebraic identity:

a² - b² = ( a + b )( a - b )

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(2x+3y+z)² - (2x-3y+z)

= (2x+3y+z+2x-3y+z)

[2x+3y+z-(2x-3y+z)]

= (4x+2z)( 2x+3y+z-2x+3y-z)

= [2(2x+z)](6y)

= 12y(2x+z)

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