Question

Descompuneti in produs de factori primi expresia(2x+5)³-8x-20.

Answer 1

(2x+5)³-8x-20=
=(2x+5)³-4(2x+5)=
=(2x+5)[(2x+5)²-4]=
=(2x+5)(4x²+20x+25-4)=
=(2x+5)(4x²+20x+21)=
=(2x+5)(4x²+14x+6x+21)=
=(2x+5)[2x(2x+7)+3(2x+7)]=
=(2x+5)(2x+7)(2x+3)

Answer 2

(2x+5)³-8x-20=
=(2x+5)³-4(2x+5)=
=(2x+5)[(2x+5)²-4]=
=(2x+5)(4x²+20x+25-4)=
=(2x+5)(4x²+20x+21)=
=(2x+5)(4x²+14x+6x+21)=
=(2x+5)[2x(2x+7)+3(2x+7)]=
=(2x+5)(2x+7)(2x+3) sper ca team ajutat ......