Question

Answer 1

a: \(A=\dfrac{x^3+2x^2+2x^2-50-5x+50}{2x\left(x+5\right)}=\dfrac{x^3+4x^2-5x}{2x\left(x+5\right)}\)

\(=\dfrac{x\left(x+5\right)\left(x-1\right)}{2x\left(x+5\right)}=\dfrac{x-1}{2}\)

Answer 2

b, tìm x để A=1

có:( x-1):2=1

x=1.2+1=3

tìm x để A=-3

có: (x-1):2=-3

x=3.2+1=7

c,Ta có:

\(P=2.\left(x+2\right).A\)

\(P=2.\left(x+2\right).\dfrac{x-1}{2}\)

\(P=2x^2+2x-2\)

tới khúc này bí:>