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\(25x^2-4y^2-4y-1=25x^2-\left(2y+1\right)^2\)
\(=\left(5x-2y-1\right)\left(5x+2y+1\right)\)
Answer:
\(25x^2-10x+4y-4y^2\)
\(=25x^2-10x+1-4x^2+4y-1\)
\(=\left(25x^2-10x+1\right)-\left(4y^2-2y+1\right)\)
\(=[\left(5x\right)^2-2.5x.1+1]-[\left(2y\right)^2-2.2y.1+1]\)
\(=\left(5x-1\right)^2-\left(2y-1\right)^2\)
\(=\left(5x-1-2y+1\right).\left(5x-1+2y-1\right)\)
\(=\left(5x-2y\right).\left(5x+2y-2\right)\)
\(-\left(x+2y\right)^2\)
\(-\left(x-3\right)^2\)
\(\left(3-5x\right)^2\)
\(-x^2-4xy-4y^2=-\left(x+2y\right)^2\)
\(-x^2+6x-9=-\left(x-3\right)^2\)
\(25x^2-30x+9=\left(5x-3\right)^2\)
a) \(=x^2-\left(2y\right)^2=\left(x-2y\right)\left(x+2y\right)\)
b) \(=x^2-\left(3y\right)^2=\left(x-3y\right)\left(x+3y\right)\)
c) \(=\left(2x-1\right)^2-\left(2y\right)^2=\left(2x-1-2y\right)\left(2x-1+2y\right)\)
d) \(=x^2-10xy+\left(5y\right)^2=\left(x-5y\right)^2\)
e) \(=\left(3x\right)^2-6x+1=\left(3x-1\right)^2\)
f) \(=\left(5x\right)^2+20x+4=\left(5x+2\right)^2\)
\(25x^2-10x+1-y^2\)
\(=\left(5x-1\right)^2-y^2\)
\(=\left(5x-y-1\right)\left(5x+y-1\right)\)
\(4y^2-4x^2-4y+1\)
\(=\left(2y-1\right)^2-\left(2x\right)^2\)
\(=\left(2y+2x-1\right)\left(2y-2x-1\right)\)
\(-y^2+6y-9+x^2\)
\(=x^2-\left(y-3\right)^2\)
\(=\left(x+y-3\right)\left(x-y+3\right)\)
a) \(4x^2-4xy+y^2-9\)
\(=\left(2x-y\right)^2-3^2\)
\(=\left(2x-y+3\right)\left(2x-y-3\right)\)
b) \(x^2-36+4xy+4y^2\)
\(=\left(4y^2+4xy+x^2\right)-36\)
\(=\left(2y+x\right)^2-6^2\)
\(=\left(2y+x+6\right)\left(2y+x-6\right)\)
c) \(9x^2-12xy-25+4y^2\)
\(=\left(9x^2-12xy+4y^2\right)-25\)
\(=\left(3x-2y\right)^2-5^2\)
\(=\left(3x-2y+5\right)\left(3x-2y-5\right)\)
d) \(25x^2+10x-4y^2+1\)
\(=\left(25x^2+10x+1\right)-4y^2\)
\(=\left(5x+1\right)^2-\left(2y\right)^2\)
\(=\left(5x+2y+1\right)\left(5x-2y+1\right)\)
\(x^2-4y^2-2x-4y\)
\(=\left(x-2y\right)\left(x+2y\right)-2\left(x+2y\right)\)
\(=\left(x+2y\right)\left(x-2y-2\right)\)
\(25x^2-4y^2-4y-1\)
\(=25x^2-\left(2y+1\right)^2=\left(5x-2y-1\right)\left(5x+2y+1\right)\)
25x2 - 4y2 - 4y - 1
= 25x2 - (4y2 + 4y + 1)
= (5x)2 - (2y + 1)2
= [5x - (2y + 1)][5x + (2y + 1)]
= (5x - 2y - 1)(5x + 2y + 1)