0.44 = 0.44
0.8 = 0.80
0.4 = 0.40 (наименьшее)
4/9 примерно 0.44
Ответ-0.4
(-2)3×(-5)3=(-6×-5×)-3=-90
A1+a1q³=30⇒a1*(1+q³)=30⇒a1=30/(1+q³)
a1q+a1q²=10⇒a1(q+q²)=10⇒a1=10/(q+q²)
30/(1+q)(1-q+q²)=10/q(1+q)
3/(1-q+q²)=1/q
1-q+q²-3q=0
q²-4q+1=0
D=16-4=12
q1=(4-2√3)/2=2-√3⇒a1=10/(9-5√3)=5(9+5√3)/3
q2=2+√3⇒a1=10/(9+5√3)=5(9-5√3)/3
1/3*2 1/2=5/6
5/6*27=22.5
22.5*3=67.5
67.5-50=17.5
Ответ:17.5