Question

1/ Tìm GTNN.

A= 25x^2 +3y^2- 10x+11

B= (x-3)^2+(x-11)^2.

2/ Phân tích thành nhân tử

a/ 9x(x-y)-10(y-x)^2

b/ x^2 -x^2- 9y^2 +3yz.

c/ 12x^3+ 4x^2- 27x-9

d/ x^3 -x^2 -5x +125

Answer 1

Bài 10:

a: \(=9x\left(x-y\right)-10\left(x-y\right)^2\)

\(=\left(x-y\right)\left(9x-10x+10y\right)\)

\(=\left(x-y\right)\left(10y-x\right)\)

c: \(=12x^3-18x^2+22x^2-33x+6x-9\)

\(=\left(2x-3\right)\left(6x^2+11x+3\right)\)

\(=\left(2x-3\right)\left(6x^2+9x+2x+3\right)\)

\(=\left(2x-3\right)\left(2x+3\right)\left(3x+1\right)\)