Question

 

Answer 1

a: Ta có: \(A=\left\lbrack3y^2\left(2y-1\right)+y+1\right\rbrack-y\left(1-y+y^2\right)-y^2+y\)

\(=6y^3-3y^2+y+1-y+y^2-y^3-y^2+y\)

\(=5y^3-3y^2+y+1\)

b: Ta có: \(B=2a\cdot x^2-a\left(1+2x^2\right)-\left\lbrack a-x\left(x+a\right)\right\rbrack\)

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

=-a-a+x(x+1)

=x(x+1)

\(=x^2+x\)

c: \(C=\left\lbrack2p^3-\left(p^3-1\right)+2p^2\left(p+3\right)-2p^3\right\rbrack\cdot\left(3p\right)^2-3p^5\)

\(=\left\lbrack-p^3+1+2p^3+6p^2\right\rbrack\cdot9p^2-3p^5\)

\(=\left\lbrack p^3+6p^2+1\right\rbrack\cdot9p^2-3p^5=9p^5+54p^4+9p^2-3p^5=6p^5+54p^4+9p^2\)