Question

Tính:

a)2x(x+5)(x-1)

b)(x-2y)(x+2y)

c)(x-1)(x^2+x+1)

Giup mik vs

Answer 1

b)(x-2y)(x+2y)

=x^2-4y^2

c)(x-1)(x^2+x+1)

=x^3-1

Giup mik vs

Answer 2

a/

\(2x\left(x+5\right)\left(x-1\right)\)

\(=\left(2x^2+10x\right)\left(x-1\right)\)

\(=2x^3-2x^2+10x^2-10x\)

\(=2x^3+8x^2-10x\)

b/

\(\left(x-2y\right)\left(x+2y\right)\)

\(=x^2-\left(2y\right)^2\)

\(=x^2-4y^2\)

c/

\(\left(x-1\right)\left(x^2+x+1\right)\)

\(=\left(x-1\right)\left(x^2+x\cdot1+1^2\right)\)

\(=x^3-1^3\)

\(=x^3-1\)