Simplify and find the value of the simplified expression when x=-1 and y=2.
`3(2x^2-4y^2)- [7xy-[3(x^3-2y^2)-2xy)]`

Simplify and find the value of the simplified expression when x=-1 and y=2. 4(x^2+3y^2)-(9xy-[5(2x^3-3y^2)+xy)]

Simplify: (x^2-2y^2)(x+4y)x^2y^2

Simplify the following expression: x^2(1-3y^2)+x(x y^2-2x)-3y(y-4x^2y)

Add x^2+y^2+3xy-6 and 2x^2-4y^2-xy+5

When x=4 and y=2 find the value of : x^(2)-2xy+y^(2)

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

Simplify each of the following algebraic expressions by removing grouping symbols. 5a-(3b-2a+4c)\ -2(x^2-y^2+x y)-3(x^2+y^2-x y)

Simplify (2y - 1) (3-4y)

Simplify each of the following expressions: (i) (x+y+z)^2+(x+y/2+z/3)^2-(x/2+y/3+z/4)^2

Find the area of the parallelogram formed by the lines 2x^2+5xy+3y^2=0 and 2x^2+5xy+3y^2+3x+4y+1=0