a, \(3x\left(x-2\right)-5x\left(1-x\right)-8\left(x^2-2\right)\)
\(=3x^2-6x-5x+5x^2-8x^2+16\)
\(=-11x+16\)
b, \(\left(4x^2-3y\right)2y-\left(3x^2-4y\right)3y\)
\(=8x^2y-6y^2-\left(9x^2y-12y^2\right)\)
\(=8x^2y-6y^2-9x^2y+12y^2=-x^2y+6y^2\)
c, \(3y^2\left[\left(2y-1\right)+y+1\right]-y\left(1-y-y^2\right)+y\)
\(=3y^2.3y-y+y^2+y^3+y\)
\(=9y^3+y^2+y^3=10y^3+y^2\)
Chúc bạn học tốt!!!
a, \(3x\left(x-2\right)-5x\left(1-x\right)-8\left(x^2-2\right)\)
\(=3x^2-6x-5x+5x^2-8x^2+16\)
\(=-11x+16\)
b, \(\left(4x^2-3y\right)2y-\left(3x^2-4y\right)3y\)
\(=8x^2y-6y^2-9x^2y+12y^2\)
\(=-x^2y+6y^2\)
c, \(3y^2\left[\left(2y-1\right)+y+1\right]-y\left(1-y-y^2\right)+y\)
\(=3y^2.3y-y\left(1-y-y^2-1\right)\)
\(=9y^3-y\left(-y-y^2\right)\)
\(=9y^3+y^2+y^3=10y^3+y^2\)
a) \(3x\left(x-2\right)-5x\left(1-x\right)-8\left(x^2-2\right)\)
\(=3x^2-6x-5x+5x^2-8x^2+16\)
\(=3x^2+5x^2-8x^2-6x-5x+16\)
\(=-11x+16\)
b) \(\left(4x^2-3y\right)2y-\left(3x^2-4y\right).3y\)
\(=9x^2y-6y^2-\left(9x^2y-12y^2\right)\)
\(=9x^2y-6y^2-9x^2y+12y^2\)
\(=9x^2y-9x^2y-6y^2+12y^2\)
\(=6y^2\)
c) \(3y^2\left[\left(2y-1\right)+y+1\right]-y\left(1-y-y^2\right)+y\)
\(=3y^2\left(2y-1\right)+3y^3+3y^2-y+y^2+y^3+y\)
\(=6y^3-3y^2+3y^3+3y^2-y+y^2+y^3+y\)
\(=6y^3+3y^3+y^3-3y^2+3y^2+y^2-y+y\)
\(=10y^3+y^2\)
