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Mathematical necessities
1. Simplify before evaluation.

-2x-{4x-2y-[3x-(2y+ 1)]}, where x=-3/2 and y=2008.

=-2x-{4x-2y-[3x-2y- 1]}

=-2x-{4x-2y-3x+2y+ 1}

=-2x-{4x-3x-2y+2y+ 1}

=-2x-{x+ 1}

=-2x-x- 1

=-3x- 1

=-3*(-3/2)- 1

=9/2- 1

=7/2

2. It is known that the m power of 2'x'y and the n power of -3x'y are similar terms, and the value of m-(m power n+3m-4n)+(m'-3n power 2n) is calculated.

The m power of x and the -3x power of y are similar terms.

That is, the m power of x = x, the 2 power of y = the n power of y.

m= 1

n=2

M-(quadratic power of' m' n+3m-4n)+(quadratic power of 2n' m'-3n)

Quadratic power of = m-' m-' m' n-3m+4n+2n' m '-3n

= m-3m+2n' m quadratic' -'m quadratic' n+4n-3n

=-2m+n' m squared' +n

The second power of =-2* 1+2* 1

=-2+2+2

=2

3. Given that the quadratic power of' A '-2ab =3 and the quadratic power of' B '-ab =4, then the quadratic power of 2' B '-' A' = ().

The quadratic power of 2' b'-'the quadratic power of a'

= 2 ('b'-quadratic power of AB)-('quadratic power of A' -=2('b)

=2*4-3

=8-3

=5