Come si espande (x-1) ^ 3 (x−1)3?
Risposta:
x^3-3x^2+3x-1x3−3x2+3x−1
Spiegazione:
"note that"note that
(x+a)^3=x^3+(a+a+a)x^2+(a.a+a.a+a.a)x+a^3(x+a)3=x3+(a+a+a)x2+(a.a+a.a+a.a)x+a3
(x-1)^3toa=-1(x−1)3→a=−1
rArr(x-1)^3=x^3+(-1-1-1)x^2+(1+1+1)x+(-1)^3⇒(x−1)3=x3+(−1−1−1)x2+(1+1+1)x+(−1)3
=x^3-3x^2+3x-1=x3−3x2+3x−1