Question

Bài 1: Thực hiện phép tính:

a) \(32x^5\left(3y-7\right)^5:[-4x\left(7-3y\right)^4]\)

b) \(\dfrac{12x^3\left(3x-5\right)^2}{4x\left(3x-5\right)^2}-\dfrac{2x\left(x+7\right)^4}{\left(x+7\right)^3}\)

Answer 1

a)\(\dfrac{32x^5\left(3y-7\right)^5}{-4x\left(7-3y\right)^4}=\dfrac{-4x.\left(-8x^4\right)\left(3y-7\right)^4\left(3y-7\right)}{-4x\left(3y-7\right)^4}\)

\(=\dfrac{\left(-8x^4\right)\left(3y-7\right)}{1}=\left(-8x^4\right)\left(3y-7\right)\)

\(=-32x^4y+56x^4\)

b) \(\dfrac{12x^3\left(3x-5\right)^2}{4x\left(3x-5\right)^2}-\dfrac{2x\left(x+7\right)}{\left(x+7\right)^3}=\dfrac{12x^3}{4x}-\dfrac{2x}{\left(x+7\right)^2}\)

\(=3x^2-\dfrac{2x}{\left(x+7\right)^2}\)

\(\)