Răspuns:
Explicație pas cu pas:
20
b1=4 si b2=2 ⇒q=b2/b1-2/4=1/2
bn=b1·q^(n-1)
b10=b1·q^9=4·(1/2)^9=1/2^7=1/128
21
b1=2 b2=4 ⇒q=b2/b1=4/2=2
b6=b1·q^5=2·2^5=2^6=64
23
f(x)=3x-1
(f(-2)=-6-1=-7 f(-1)=-3-1=-4 f(0)=-1 f(1)=2
f(-2)+f(-1)+f(0)+f(1)=-7-4-1+2=-12+2=-10
