Question

Phân tích thành nhân tử : x³(x²-7)²-36x

Answer 1

\(=x^3\left(x^4-14x^2+49\right)-36x\)

\(=x^7-14x^5+49x^3-36x\)

\(=x^7-x^5-13x^5+13x^3+36x^3-36x\)

\(=x^5\left(x^2-1\right)-13x^3\left(x^2-1\right)+36x\left(x^2-1\right)\)

\(=x\left(x^2-1\right)\left(x^4-13x^2+36\right)\)

\(=x\left(x-1\right)\left(x+1\right)\left(x^4-13x^2+36\right)\)

Answer 2

x\(^3\)(x\(^2\)-7)\(^2\) -36x

<=> x [ x\(^2\) (x\(^2\) -7)\(^2\) -36]

<=>x{[x(x\(^2\) -7)]\(^2\) -6\(^2\) }

<=> x[ (x\(^3\) -7x)\(^2\) -6\(^2\) ]

<=> x (x\(^3\) -7x-6)(x\(^3\) -7x +6)