Simplify: `(2x-5y)^3-\ (2x+5y)^3`

Simplify: 2x-6x(5-8x-3y)

Simplify : (2x+y)^3+(x-y)^3 .

Simplify : (3x+2y)^3-(5x+y)^3 .

Simplify : (2x+y)^(5)-5y(2x+y)^(4)+10y^(2)(2x+y)^(3)-10y^(3)(2x+y)^(2)+5y^(4)(2x+y)-y^(5)

Simplify : (i) (5x - 9y) - (-7x + y) (ii) (x^(2) -x) -(1)/(2)(x - 3 + 3x^(2)) (iii) [7 - 2x + 5y - (x -y)]-(5x + 3y -7) (iv) ((1)/(3)y^(2) - (4)/(7)y + 5) - ((2)/(7)y - (2)/(3)y^(2) + 2) - ((1)/(7)y - 3 + 2y^(2))

Simplify: (3x+2y)(4x+3y)-\ (2x-y)(7x-3y)

Simplify: (2x + 5y)(3x + 4y) - (7x + 3y)(2x + y)

Simplify: 5 (x + 3y) -2 (3x-4y)