tentukan hasil perkalian : c. (x - 5 ) (x pangkat2 - 4x +20) #jwbdengancaranya

(x-5)(x²-4x+20)=x³-4x²+20x-5x²+20x-100
                     =x³-4x²-5x²+20x+20x-100
                     =x³-9x²+40x-100

maaf kalau salah ;)

= (x-5)(x²-4x+20)
= x(x²-4x+20)-5(x²=4x+20)
= x³-4x²+20x-5x+20x-5x²+20x-100
= x³-4x²-5x²+20x+20x-100
= x³-9x²+40x-100