Question

(5x-1)^2 + (5x+1)^2-2(25x^2-1)

Answer 1

\(=\left(5x-1\right)^2+\left(5x+1\right)^2-2\left(5x-1\right)\left(5x+1\right)\)

\(=\left(5x-1-5x-1\right)^2\)

\(=\left(-2\right)^2=4\)

Answer 2

(5x-1)²+(5x+1)²-2(25x²-1)=(5x-1)²+(5x+1)²-2(5²x²-1²)

=(5x-1)²+(5x+1)²-2[(5x²)-1²]

=(5x-1)²+(5x+1)²-2(5x-1)(5x+1)

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

=(5x-1)(5x-1-5x+1)+(5x+1)(5x+1-5x-1)

=(5x-1).0+(5x+1).0

=0+0

=0

Answer 3

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