Răspuns:
Explicație pas cu pas:
b1=1 q=4
a) b3=b1×q²=1×416
b4=b3×q=16×4=64
b9=b1×q^(9-1)=4^8
b100=b1×q^99=4^99
b)S10=b1(q^10-1)/(q-1)=1×(4^10-1)/(4-1)=(4^10-1)/3
6
a)b3=16=b1×q²
b6=b1×q^5=1024 b6/b3=q^(5-2)=q³=1024/16=64 ⇒q=∛64=2
b) b3=b1×q²=16=b1×2² ⇒b1=16/4=4
b4=b3×q=16×2=32
c)S6=b1(2^6-1)/(2-1)=4×(64-1)/1=4×63=252
7
(3x-6)²=3×147 ⇒(3x-6)²=441 ⇒(3x-6)²=21² 3x=27 x1=9
3x-6=-21 3x=-15 x2=-5
