Ответ:
Объяснение: вот формулы loga(MN)=logaM+logaN
loga(M/N)=logaM-logaN
log3(7*3:(21/4))= log3(4)
A1+a1+d+a1+2d=21⇒3a1+3d=21⇒a1+d=7⇒d=7-a1
{a1+d-1=a1q⇒a1+7-a1-1=a1q⇒a1q=6
a1+2d+1=a1q²⇒a1+14-2a1+1=a1q²⇒a1q²=15-a1
15-a1=6q
q=(15-a1)/6
a1(15-a1)/6=6
15a1-a1²=36
a1²-15a1+36=0
(a1)1+(a1)2=15 U (a1)1*(a1)2=36
(a1)1=3⇒d1=7-3=4
(a1)2=12⇒d2=7-12=-5
Ответ 3;7;11 или 12;7;2
[tex] \frac{ \frac{sina}{cosa} + \frac{cosa}{cosa} }{ \frac{cosa}{sina} + \frac{sina}{sina} } =
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